common: Drop linux/delay.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/ls1021atsn/ls1021atsn.c b/board/freescale/ls1021atsn/ls1021atsn.c
index 0f94099..b05037d 100644
--- a/board/freescale/ls1021atsn/ls1021atsn.c
+++ b/board/freescale/ls1021atsn/ls1021atsn.c
@@ -11,6 +11,7 @@
 #include <asm/arch/immap_ls102xa.h>
 #include <asm/arch/ls102xa_soc.h>
 #include <asm/arch/fsl_serdes.h>
+#include <linux/delay.h>
 #include "../common/sleep.h"
 #include <fsl_validate.h>
 #include <fsl_immap.h>