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/drivers/clk/rockchip/clk_pll.c b/drivers/clk/rockchip/clk_pll.c
index 6dab509..83d45c7 100644
--- a/drivers/clk/rockchip/clk_pll.c
+++ b/drivers/clk/rockchip/clk_pll.c
@@ -12,6 +12,7 @@
 #include <asm/arch-rockchip/clock.h>
 #include <asm/arch-rockchip/hardware.h>
 #include <div64.h>
+#include <linux/delay.h>
 
 static struct rockchip_pll_rate_table rockchip_auto_table;