Disintegrate asm/system.h for Blackfin [ver #2]

Disintegrate asm/system.h for Blackfin.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: uclinux-dist-devel@blackfin.uclinux.org
Signed-off-by: Bob Liu <lliubbo@gmail.com>
diff --git a/arch/blackfin/include/asm/atomic.h b/arch/blackfin/include/asm/atomic.h
index 54c6e28..c8db653 100644
--- a/arch/blackfin/include/asm/atomic.h
+++ b/arch/blackfin/include/asm/atomic.h
@@ -7,6 +7,8 @@
 #ifndef __ARCH_BLACKFIN_ATOMIC__
 #define __ARCH_BLACKFIN_ATOMIC__
 
+#include <asm/cmpxchg.h>
+
 #ifdef CONFIG_SMP
 
 #include <linux/linkage.h>