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/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
index b3c597e..a636cff 100644
--- a/drivers/watchdog/mtk_wdt.c
+++ b/drivers/watchdog/mtk_wdt.c
@@ -11,6 +11,7 @@
 #include <hang.h>
 #include <wdt.h>
 #include <asm/io.h>
+#include <linux/bitops.h>
 
 #define MTK_WDT_MODE			0x00
 #define MTK_WDT_LENGTH			0x04