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/power/regulator/bd71837.c b/drivers/power/regulator/bd71837.c
index 850b533..931d753 100644
--- a/drivers/power/regulator/bd71837.c
+++ b/drivers/power/regulator/bd71837.c
@@ -8,6 +8,7 @@
 #include <common.h>
 #include <dm.h>
 #include <log.h>
+#include <linux/bitops.h>
 #include <power/bd71837.h>
 #include <power/pmic.h>
 #include <power/regulator.h>