forbid asm/bitops.h direct inclusion

forbid asm/bitops.h direct inclusion

Because of compile errors that may occur after bit changes if asm/bitops.h is
included directly without e.g.  linux/kernel.h which includes linux/bitops.h,
forbid direct inclusion of asm/bitops.h.  Thanks to Adrian Bunk.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-sh64/bitops.h b/include/asm-sh64/bitops.h
index 444d5ea..600c59e 100644
--- a/include/asm-sh64/bitops.h
+++ b/include/asm-sh64/bitops.h
@@ -13,6 +13,11 @@
  */
 
 #ifdef __KERNEL__
+
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
 #include <linux/compiler.h>
 #include <asm/system.h>
 /* For __swab32 */