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/ddr/fsl/main.c b/drivers/ddr/fsl/main.c
index 8533b28..84139b8 100644
--- a/drivers/ddr/fsl/main.c
+++ b/drivers/ddr/fsl/main.c
@@ -16,6 +16,7 @@
 #include <fsl_ddr.h>
 #include <init.h>
 #include <log.h>
+#include <asm/bitops.h>
 
 /*
  * CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY is the physical address from the view