ARM: OMAP: omap2plus_defconfig: Enable EXT4 support

On OMAP boards that includes an SD card slot, an EXT4 partition could
be used to store the root file system. So, the kernel should have
built-in support for EXT4 to be able to mount the VFS root on boot.
Signed-off-by: Javier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/configs/omap2plus_defconfig

@@ -197,6 +197,7 @@ CONFIG_RTC_DRV_TWL4030=y
 CONFIG_EXT2_FS=y
 CONFIG_EXT3_FS=y
 # CONFIG_EXT3_FS_XATTR is not set
+CONFIG_EXT4_FS=y
 CONFIG_QUOTA=y
 CONFIG_QFMT_V2=y
 CONFIG_MSDOS_FS=y