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/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
index 3efa8db..c00a05a 100644
--- a/drivers/spi/davinci_spi.c
+++ b/drivers/spi/davinci_spi.c
@@ -16,6 +16,7 @@
 #include <asm/arch/hardware.h>
 #include <dm.h>
 #include <dm/platform_data/spi_davinci.h>
+#include <linux/delay.h>
 
 /* SPIGCR0 */
 #define SPIGCR0_SPIENA_MASK	0x1