ARM: mvebu: Correct SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR usage

As the code is today, we get a warning about "select" statements on
"choice" options not doing anything. However, it also works as intended
because SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR is the default option
within that choice statement. To guard against future regressions, make
the choice statement in common/spl/Kconfig have an explicit default if
MVEBU_SPL_BOOT_DEVICE_MMC.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/arch/arm/mach-mvebu/Kconfig b/arch/arm/mach-mvebu/Kconfig
index 22180b0..b76510a 100644
--- a/arch/arm/mach-mvebu/Kconfig
+++ b/arch/arm/mach-mvebu/Kconfig
@@ -394,7 +394,6 @@
 	imply SPL_LIBDISK_SUPPORT
 	imply SPL_MMC
 	select SUPPORT_EMMC_BOOT if SPL_MMC
-	select SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR if SPL_MMC
 	select SPL_BOOTROM_SUPPORT
 
 config MVEBU_SPL_BOOT_DEVICE_SATA
diff --git a/common/spl/Kconfig b/common/spl/Kconfig
index c08045f..3282e08 100644
--- a/common/spl/Kconfig
+++ b/common/spl/Kconfig
@@ -537,6 +537,7 @@
 
 choice
 	prompt "Method for locating next phase of boot (e.g. U-Boot)"
+	default SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR if MVEBU_SPL_BOOT_DEVICE_MMC
 
 config SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR
 	bool "MMC raw mode: by sector"