armv7/exynos5420: Clean up unused header and constants in spi.c

Remove unused header and constant definition in SPI module.

Change-Id: I339e603f48186e4a356e83518b0d0b4c907f11b8
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3709
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/cpu/samsung/exynos5420/spi.c

@@ -22,11 +22,9 @@
 #include <arch/io.h>
 #include <stdlib.h>
 #include <assert.h>
-#include "gpio.h"
-#include "clk.h"
+
 #include "spi.h"
 
-#define OM_STAT		(0x1f << 1)
 #define EXYNOS_BASE_SPI1 ((void *)0x12d30000)
 
 #if defined(CONFIG_DEBUG_SPI) && CONFIG_DEBUG_SPI