Disintegrate asm/system.h for Hexagon

Disintegrate asm/system.h for Hexagon.  Not compiled.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Richard Kuo <rkuo@codeaurora.org>
cc: linux-hexagon@vger.kernel.org
diff --git a/arch/hexagon/include/asm/atomic.h b/arch/hexagon/include/asm/atomic.h
index e220f90..3e258043 100644
--- a/arch/hexagon/include/asm/atomic.h
+++ b/arch/hexagon/include/asm/atomic.h
@@ -23,6 +23,7 @@
 #define _ASM_ATOMIC_H
 
 #include <linux/types.h>
+#include <asm/cmpxchg.h>
 
 #define ATOMIC_INIT(i)		{ (i) }
 #define atomic_set(v, i)	((v)->counter = (i))