Disintegrate asm/system.h for ARM

Disintegrate asm/system.h for ARM.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: linux-arm-kernel@lists.infradead.org
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 9275828..bae7eb6 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -26,7 +26,6 @@
 #include <linux/types.h>
 #include <asm/byteorder.h>
 #include <asm/memory.h>
-#include <asm/system.h>
 #include <asm-generic/pci_iomap.h>
 
 /*
@@ -99,6 +98,7 @@
 
 /* IO barriers */
 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
+#include <asm/barrier.h>
 #define __iormb()		rmb()
 #define __iowmb()		wmb()
 #else