bsps: Move sbrk.c to bsps

This patch is a part of the BSP source reorganization.

Update #3285.

bsps/shared/start/sbrk.c

@@ -0,0 +1,28 @@
+/*
+ *  sbrk.c
+ *
+ *  If the BSP wants to dynamically allocate the memory for the
+ *  C Library heap (malloc) and/or be able to extend the heap,
+ *  then this routine must be functional.  This is the default
+ *  implementation which raises an error.
+ *
+ *  COPYRIGHT (c) 1989-1999.
+ *  On-Line Applications Research Corporation (OAR).
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.org/license/LICENSE.
+ */
+
+#include <rtems.h>
+
+#include <signal.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+void * sbrk(ptrdiff_t incr)
+{
+  errno = ENOMEM;
+  return (void *)-1;
+}