kbuild: unify cmd_dt_S_dtb and cmd_dt_S_dtbo

cmd_dt_S_dtb and cmd_dt_S_dtbo are almost the same; the only difference
is the prefix of the begin/end symbols. (__dtb vs __dtbo)

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

scripts/Makefile.lib

@@ -368,40 +368,25 @@ DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
 DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
 
 # Generate an assembly file to wrap the output of the device tree compiler
-quiet_cmd_dt_S_dtb= DTBS    $@
-cmd_dt_S_dtb=						\
-{							\
-	echo '\#include <asm-generic/vmlinux.lds.h>'; 	\
-	echo '.section .dtb.init.rodata,"a"';		\
-	echo '.balign STRUCT_ALIGNMENT';		\
-	echo '.global __dtb_$(subst -,_,$(*F))_begin';	\
-	echo '__dtb_$(subst -,_,$(*F))_begin:';		\
-	echo '.incbin "$<" ';				\
-	echo '__dtb_$(subst -,_,$(*F))_end:';		\
-	echo '.global __dtb_$(subst -,_,$(*F))_end';	\
-	echo '.balign STRUCT_ALIGNMENT'; 		\
-} > $@
+quiet_cmd_wrap_S_dtb = WRAP    $@
+      cmd_wrap_S_dtb = {								\
+		symbase=__$(patsubst .%,%,$(suffix $<))_$(subst -,_,$(notdir $*));	\
+		echo '\#include <asm-generic/vmlinux.lds.h>';				\
+		echo '.section .dtb.init.rodata,"a"';					\
+		echo '.balign STRUCT_ALIGNMENT';					\
+		echo ".global $${symbase}_begin";					\
+		echo "$${symbase}_begin:";						\
+		echo '.incbin "$<" ';							\
+		echo ".global $${symbase}_end";						\
+		echo "$${symbase}_end:";						\
+		echo '.balign STRUCT_ALIGNMENT';					\
+	} > $@
 
 $(obj)/%.dtb.S: $(obj)/%.dtb FORCE
-	$(call if_changed,dt_S_dtb)
-
-# Generate an assembly file to wrap the output of the device tree compiler
-quiet_cmd_dt_S_dtbo= DTBOS   $@
-cmd_dt_S_dtbo=						\
-{							\
-	echo '\#include <asm-generic/vmlinux.lds.h>';	\
-	echo '.section .dtb.init.rodata,"a"';		\
-	echo '.balign STRUCT_ALIGNMENT';		\
-	echo '.global __dtbo_$(subst -,_,$(*F))_begin';	\
-	echo '__dtbo_$(subst -,_,$(*F))_begin:';	\
-	echo '.incbin "$<" ';				\
-	echo '__dtbo_$(subst -,_,$(*F))_end:';		\
-	echo '.global __dtbo_$(subst -,_,$(*F))_end';	\
-	echo '.balign STRUCT_ALIGNMENT';		\
-} > $@
+	$(call if_changed,wrap_S_dtb)
 
 $(obj)/%.dtbo.S: $(obj)/%.dtbo FORCE
-	$(call if_changed,dt_S_dtbo)
+	$(call if_changed,wrap_S_dtb)
 
 quiet_cmd_dtc = DTC     $@
 cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \