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/spi/mxs_spi.c b/drivers/spi/mxs_spi.c
index 635955e..0da4a80 100644
--- a/drivers/spi/mxs_spi.c
+++ b/drivers/spi/mxs_spi.c
@@ -19,6 +19,7 @@
 #include <memalign.h>
 #include <spi.h>
 #include <asm/cache.h>
+#include <linux/bitops.h>
 #include <linux/errno.h>
 #include <asm/io.h>
 #include <asm/arch/clock.h>