--- zzzz-none-000/linux-4.9.276/arch/mips/boot/dts/brcm/Makefile	2021-07-20 14:21:16.000000000 +0000
+++ falcon-5530-750/linux-4.9.276/arch/mips/boot/dts/brcm/Makefile	2023-04-05 08:19:00.000000000 +0000
@@ -33,10 +33,4 @@
 	bcm97425svmb.dtb \
 	bcm97435svmb.dtb
 
-obj-y				+= $(patsubst %.dtb, %.dtb.o, $(dtb-y))
-
-# Force kbuild to make empty built-in.o if necessary
-obj-				+= dummy.o
-
-always				:= $(dtb-y)
-clean-files			:= *.dtb *.dtb.S
+obj-$(CONFIG_BUILTIN_DTB)	+= $(addsuffix .o, $(dtb-y))