arch: Add Cmake build support for raspberrypi-4b board & bcm2711 chip

Add:
arch/arm64/src/bcm2711/CMakeLists.txt
boards/arm64/bcm2711/raspberrypi-4b/CMakeLists.txt
boards/arm64/bcm2711/raspberrypi-4b/src/CMakeLists.txt

arch/arm64/src/bcm2711/CMakeLists.txt

@@ -0,0 +1,43 @@
+# ##############################################################################
+# arch/arm64/src/bcm2711/CMakeLists.txt
+#
+# 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
+# file to you under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License.  You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations under
+# the License.
+#
+# ##############################################################################
+
+# BCM2711 specific C source files
+
+set(SRCS bcm2711_boot.c bcm2711_serial.c bcm2711_gpio.c bcm2711_timer.c)
+
+# Early boot logging
+
+if(CONFIG_ARCH_EARLY_PRINT)
+  list(APPEND SRCS bcm2711_lowputc.c)
+endif()
+
+# I2C interfaces
+
+if(CONFIG_BCM2711_I2C)
+  list(APPEND SRCS bcm2711_i2c.c)
+endif()
+
+# SPI interfaces
+#
+if(CONFIG_BCM2711_SPI)
+  list(APPEND SRCS bcm2711_spi.c)
+endif()
+
+target_sources(arch PRIVATE ${SRCS})