sched: migrate to SPDX identifier

Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.

Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>

sched/irq/CMakeLists.txt

@@ -1,6 +1,8 @@
 # ##############################################################################
 # sched/irq/CMakeLists.txt
 #
+# SPDX-License-Identifier: Apache-2.0
+#
 # Licensed to the Apache Software Foundation (ASF) under one or more contributor
 # license agreements.  See the NOTICE file distributed with this work for
 # additional information regarding copyright ownership.  The ASF licenses this

sched/irq/Make.defs

@@ -1,6 +1,8 @@
 ############################################################################
 # sched/irq/Make.defs
 #
+# SPDX-License-Identifier: Apache-2.0
+#
 # Licensed to the Apache Software Foundation (ASF) under one or more
 # contributor license agreements.  See the NOTICE file distributed with
 # this work for additional information regarding copyright ownership.  The

sched/irq/irq.h

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq.h
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_attach.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_attach.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_attach_thread.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_attach_thread.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_attach_wqueue.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_attach_wqueue.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_chain.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_chain.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_csection.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_csection.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_dispatch.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_dispatch.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_foreach.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_foreach.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_initialize.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_initialize.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_procfs.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_procfs.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_spinlock.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_spinlock.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The

sched/irq/irq_unexpectedisr.c

@@ -1,6 +1,8 @@
 /****************************************************************************
  * sched/irq/irq_unexpectedisr.c
  *
+ * SPDX-License-Identifier: Apache-2.0
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The