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/gpio/mt7621_gpio.c b/drivers/gpio/mt7621_gpio.c
index 54d313d..612413e 100644
--- a/drivers/gpio/mt7621_gpio.c
+++ b/drivers/gpio/mt7621_gpio.c
@@ -12,6 +12,7 @@
 #include <errno.h>
 #include <fdtdec.h>
 #include <malloc.h>
+#include <linux/bitops.h>
 #include <linux/io.h>
 #include <asm/io.h>
 #include <asm/gpio.h>