Disintegrate asm/system.h for M32R

Disintegrate asm/system.h for M32R.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-m32r@ml.linux-m32r.org
diff --git a/arch/m32r/include/asm/spinlock.h b/arch/m32r/include/asm/spinlock.h
index b0ea2f2..fa13694 100644
--- a/arch/m32r/include/asm/spinlock.h
+++ b/arch/m32r/include/asm/spinlock.h
@@ -11,6 +11,7 @@
 
 #include <linux/compiler.h>
 #include <linux/atomic.h>
+#include <asm/dcache_clear.h>
 #include <asm/page.h>
 
 /*