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/usb/host/ehci-vf.c b/drivers/usb/host/ehci-vf.c
index ba6eeca..562207d 100644
--- a/drivers/usb/host/ehci-vf.c
+++ b/drivers/usb/host/ehci-vf.c
@@ -19,6 +19,7 @@
 #include <asm/arch/crm_regs.h>
 #include <asm/mach-imx/iomux-v3.h>
 #include <asm/mach-imx/regs-usbphy.h>
+#include <linux/delay.h>
 #include <usb/ehci-ci.h>
 #include <linux/libfdt.h>
 #include <fdtdec.h>