remove libc_errno.h & libc_limits.h

examples/libc/ex3.c

@@ -9,7 +9,7 @@
 /* Multi-thread searching.
    Illustrates: thread cancellation, cleanup handlers. */
 
-#include <errno.h>
+#include <sys/errno.h>
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>

examples/libc/ex6.c

@@ -6,7 +6,7 @@
  * Change Logs:
  * Date           Author       Notes
  */
-#include <errno.h>
+#include <sys/errno.h>
 #include <stdio.h>
 #include <string.h>
 #include <pthread.h>

examples/libc/ex7.c

@@ -11,7 +11,7 @@
  * Test case that illustrates a timed wait on a condition variable.
  */
 
-#include <errno.h>
+#include <sys/errno.h>
 #include <stdio.h>
 #include <string.h>
 #include <pthread.h>

examples/libc/file.c

@@ -11,7 +11,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <finsh.h>
-#include <errno.h>
+#include <sys/errno.h>
 #include <sys/fcntl.h>
 #include <sys/stat.h>
 

examples/libc/memory.c

@@ -11,7 +11,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <finsh.h>
-#include <errno.h>
+#include <sys/errno.h>
 
 static int errors = 0;
 static void merror(const char *msg)