common: Drop linux/bitops.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/net/ftgmac100.h b/drivers/net/ftgmac100.h
index 9a789e4..f7874ae 100644
--- a/drivers/net/ftgmac100.h
+++ b/drivers/net/ftgmac100.h
@@ -13,6 +13,7 @@
 #define __FTGMAC100_H
 
 /* The registers offset table of ftgmac100 */
+#include <linux/bitops.h>
 struct ftgmac100 {
 	unsigned int	isr;		/* 0x00 */
 	unsigned int	ier;		/* 0x04 */