arm: Don't include common.h in header files

It is bad practice to include common.h in other header files since it can
bring in any number of superfluous definitions. It implies that some C
files don't include it and thus may be missing CONFIG options that are set
up by that file. The C files should include these themselves.

Update some header files in arch/arm to drop this.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/board/overo/spl.c b/board/overo/spl.c
index d577e00..91d8091 100644
--- a/board/overo/spl.c
+++ b/board/overo/spl.c
@@ -11,6 +11,8 @@
  * (C) Copyright 2004-2008
  * Texas Instruments, <www.ti.com>
  */
+
+#include <common.h>
 #include <asm/io.h>
 #include <asm/arch/mem.h>
 #include <asm/arch/sys_proto.h>