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/arch/arm/mach-uniphier/dram/umc-pxs2.c b/arch/arm/mach-uniphier/dram/umc-pxs2.c
index 7de6b7f..3f7e5f3 100644
--- a/arch/arm/mach-uniphier/dram/umc-pxs2.c
+++ b/arch/arm/mach-uniphier/dram/umc-pxs2.c
@@ -9,6 +9,7 @@
 
 #include <init.h>
 #include <log.h>
+#include <linux/bitops.h>
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/io.h>