brcm63xx: make use of the new BuildDTB command

Now that we have a BuildDTB command, make use of it instead of calling
dtc directly.

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

SVN-Revision: 46390

target/linux/brcm63xx/image/Makefile

@@ -198,7 +198,7 @@ endef
 
 define Image/PrepareCFELzmaKernelDTB
 	# compile the dts (the dtb will be later reused for the lzma loader)
-	$(LINUX_DIR)/scripts/dtc/dtc -O dtb -o $(DTS_DIR)/$(1).dtb ../dts/$(1).dts
+	$(call Image/BuildDTB,../dts/$(1).dts,$(DTS_DIR)/$(1).dtb)
 	cat $(KDIR)/vmlinux $(DTS_DIR)/$(1).dtb > $(KDIR)/vmlinux-$(1)
 	$(call Image/PrepareCFELzmaKernel,-$(1))
 	rm -f $(KDIR)/vmlinux-$(1)