ARM: keystone2: Use dtb images by default

Now that OF_CONTROL is enabled on all keystone2 platforms,
build the default images with DT.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/arch/arm/mach-keystone/config.mk b/arch/arm/mach-keystone/config.mk
index ceacffa..9ae1e9a 100644
--- a/arch/arm/mach-keystone/config.mk
+++ b/arch/arm/mach-keystone/config.mk
@@ -16,13 +16,13 @@
 
 OBJCOPYFLAGS_u-boot-spi.gph = -I binary -O binary --pad-to=$(CONFIG_SPL_PAD_TO) \
 			  --gap-fill=0
-u-boot-spi.gph: spl/u-boot-spl.gph u-boot.img FORCE
+u-boot-spi.gph: spl/u-boot-spl.gph u-boot-dtb.img FORCE
 	$(call if_changed,pad_cat)
 
 ifndef CONFIG_SPL_BUILD
 MKIMAGEFLAGS_MLO = -A $(ARCH) -T gpimage -C none \
 	-a $(CONFIG_SYS_TEXT_BASE) -e $(CONFIG_SYS_TEXT_BASE) -n U-Boot
-MLO: u-boot.bin FORCE
+MLO: u-boot-dtb.bin FORCE
 	$(call if_changed,mkimage)
 	@dd if=/dev/zero bs=8 count=1 2>/dev/null >> $@
 endif