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/board/freescale/lx2160a/lx2160a.c b/board/freescale/lx2160a/lx2160a.c
index fba068c..88eb66b 100644
--- a/board/freescale/lx2160a/lx2160a.c
+++ b/board/freescale/lx2160a/lx2160a.c
@@ -16,6 +16,7 @@
 #include <fsl_sec.h>
 #include <asm/io.h>
 #include <fdt_support.h>
+#include <linux/bitops.h>
 #include <linux/libfdt.h>
 #include <fsl-mc/fsl_mc.h>
 #include <env_internal.h>