ARM: mach-msm: fix compile fail from system.h fallout

To fix:

  In file included from arm/boot/compressed/misc.c:28:0:
  arm/mach-msm/include/mach/uncompress.h: In function 'putc':
  arch/arm/mach-msm/include/mach/uncompress.h:48:3: error: implicit
  declaration of function 'smp_mb' [-Werror=implicit-function-declaration]

The putc does a cpu_relax which for this platform is smp_mb.

Bisect indicates the 1st failing commit as: 0195c00244dc ("Merge tag
'split-asm_system_h...")

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/arm/mach-msm/include/mach/uncompress.h b/arch/arm/mach-msm/include/mach/uncompress.h
index 169a840..c14011f 100644
--- a/arch/arm/mach-msm/include/mach/uncompress.h
+++ b/arch/arm/mach-msm/include/mach/uncompress.h
@@ -16,6 +16,7 @@
 #ifndef __ASM_ARCH_MSM_UNCOMPRESS_H
 #define __ASM_ARCH_MSM_UNCOMPRESS_H
 
+#include <asm/barrier.h>
 #include <asm/processor.h>
 #include <mach/msm_iomap.h>