spl: Kconfig: Replace CONFIG_SPL_EXT_SUPPORT to CONFIG_SPL_FS_EXT4

Replace CONFIG_SPL_EXT_SUPPORT to CONFIG_SPLY_FS_EXT4 so both
obj-$(CONFIG_$(SPL_)FS_EXT4) and CONFIG_IS_ENABLED(FS_EXT4) can be
used to control the build in both SPL and U-Boot.

Signed-off-by: Tien Fong Chee <tien.fong.chee@intel.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index f0c2d21..1cac443 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -13,7 +13,7 @@
 	select ARM_ERRATA_725233
 	select USE_TINY_PRINTF
 	imply NAND_OMAP_GPMC
-	imply SPL_EXT_SUPPORT
+	imply SPL_FS_EXT4
 	imply SPL_FS_FAT
 	imply SPL_GPIO_SUPPORT
 	imply SPL_I2C_SUPPORT
@@ -35,7 +35,7 @@
 	imply NAND_OMAP_ELM
 	imply NAND_OMAP_GPMC
 	imply SPL_DISPLAY_PRINT
-	imply SPL_EXT_SUPPORT
+	imply SPL_FS_EXT4
 	imply SPL_FS_FAT
 	imply SPL_GPIO_SUPPORT
 	imply SPL_I2C_SUPPORT
@@ -59,7 +59,7 @@
 	imply NAND_OMAP_GPMC
 	imply SPL_DISPLAY_PRINT
 	imply SPL_ENV_SUPPORT
-	imply SPL_EXT_SUPPORT
+	imply SPL_FS_EXT4
 	imply SPL_FS_FAT
 	imply SPL_GPIO_SUPPORT
 	imply SPL_I2C_SUPPORT