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/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
index 97188b2..3306bd8 100644
--- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c
+++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
@@ -10,6 +10,7 @@
 #include <log.h>
 #include <nand.h>
 #include <reset.h>
+#include <linux/bitops.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/iopoll.h>