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/ram/stm32_sdram.c b/drivers/ram/stm32_sdram.c
index 1894a60..3fddf4d 100644
--- a/drivers/ram/stm32_sdram.c
+++ b/drivers/ram/stm32_sdram.c
@@ -12,6 +12,7 @@
 #include <ram.h>
 #include <asm/io.h>
 #include <dm/device_compat.h>
+#include <linux/bitops.h>
 #include <linux/delay.h>
 
 #define MEM_MODE_MASK	GENMASK(2, 0)