arch:exynos: boot mode: add get_boot_mode(), code cleanup

This patch introduces code clean-up for exynos boot mode check.
It includes:
- removal of typedef: boot_mode
- move the boot mode enum to arch-exynos/power.h
- add bootmode for sequence: eMMC 4.4 ch4 / SD ch2
- add new function: get_boot_mode() for OM[5:1] pin check
- update spl boot code

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>

Changes v5:
- exynos: boot mode: add missing bootmode (1st:EMMC 4.4 / 2nd:SD ch2)

Changes v6:
- none

changes v7:
- change boot mode name: BOOT_MODE_MMC to BOOT_MODE_SD
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/arch/arm/include/asm/arch-exynos/spl.h b/arch/arm/include/asm/arch-exynos/spl.h
index b1d68c3..cdcb2bc 100644
--- a/arch/arm/include/asm/arch-exynos/spl.h
+++ b/arch/arm/include/asm/arch-exynos/spl.h
@@ -8,20 +8,7 @@
 #define __ASM_ARCH_EXYNOS_SPL_H__
 
 #include <asm/arch-exynos/dmc.h>
-
-enum boot_mode {
-	/*
-	 * Assign the OM pin values for respective boot modes.
-	 * Exynos4 does not support spi boot and the mmc boot OM
-	 * pin values are the same across Exynos4 and Exynos5.
-	 */
-	BOOT_MODE_MMC = 4,
-	BOOT_MODE_EMMC = 8,     /* EMMC4.4 */
-	BOOT_MODE_SERIAL = 20,
-	/* Boot based on Operating Mode pin settings */
-	BOOT_MODE_OM = 32,
-	BOOT_MODE_USB,	/* Boot using USB download */
-};
+#include <asm/arch/power.h>
 
 #ifndef __ASSEMBLY__
 /* Parameters of early board initialization in SPL */
@@ -62,7 +49,7 @@
 	 * table only for mmc boot.
 	 */
 	u32		uboot_size;
-	enum boot_mode	boot_source;	/* Boot device */
+	unsigned	boot_source;	/* Boot device */
 	unsigned	frequency_mhz;	/* Frequency of memory in MHz */
 	unsigned	arm_freq_mhz;	/* ARM Frequency in MHz */
 	u32		serial_base;	/* Serial base address */