nds32: Convert Makefiles to use COBJS-y style

Signed-off-by: Kuan-Yu Kuo <ken.kuoky@gmail.com>
Cc: Macpaul Lin <macpaul@gmail.com>
diff --git a/arch/nds32/cpu/n1213/Makefile b/arch/nds32/cpu/n1213/Makefile
index da15574..7e80082 100644
--- a/arch/nds32/cpu/n1213/Makefile
+++ b/arch/nds32/cpu/n1213/Makefile
@@ -31,8 +31,8 @@
 
 START	= start.o
 
-SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(COBJS) $(SOBJS))
+SRCS	:= $(START:.o=.S) $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS-y) $(SOBJS-y))
 START	:= $(addprefix $(obj),$(START))
 
 all:	$(obj).depend $(START) $(LIB)
diff --git a/arch/nds32/cpu/n1213/ag101/Makefile b/arch/nds32/cpu/n1213/ag101/Makefile
index 8716c4e..737a972 100644
--- a/arch/nds32/cpu/n1213/ag101/Makefile
+++ b/arch/nds32/cpu/n1213/ag101/Makefile
@@ -33,15 +33,15 @@
 COBJS-y	:= cpu.o timer.o
 
 ifndef CONFIG_SKIP_LOWLEVEL_INIT
-SOBJS	:= lowlevel_init.o
+SOBJS-y	:= lowlevel_init.o
 endif
 
 ifndef CONFIG_SKIP_TRUNOFF_WATCHDOG
-SOBJS	+= watchdog.o
+SOBJS-y	+= watchdog.o
 endif
 
-SRCS	:= $(SOBJS:.o=.S) $(COBJS-y:.o=.c)
-OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS-y))
+SRCS	:= $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
 
 all:	$(obj).depend $(LIB)
 
diff --git a/arch/nds32/cpu/n1213/ag102/Makefile b/arch/nds32/cpu/n1213/ag102/Makefile
index 8716c4e..737a972 100644
--- a/arch/nds32/cpu/n1213/ag102/Makefile
+++ b/arch/nds32/cpu/n1213/ag102/Makefile
@@ -33,15 +33,15 @@
 COBJS-y	:= cpu.o timer.o
 
 ifndef CONFIG_SKIP_LOWLEVEL_INIT
-SOBJS	:= lowlevel_init.o
+SOBJS-y	:= lowlevel_init.o
 endif
 
 ifndef CONFIG_SKIP_TRUNOFF_WATCHDOG
-SOBJS	+= watchdog.o
+SOBJS-y	+= watchdog.o
 endif
 
-SRCS	:= $(SOBJS:.o=.S) $(COBJS-y:.o=.c)
-OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS-y))
+SRCS	:= $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
 
 all:	$(obj).depend $(LIB)
 
diff --git a/arch/nds32/lib/Makefile b/arch/nds32/lib/Makefile
index 705e1ff..022b21a 100644
--- a/arch/nds32/lib/Makefile
+++ b/arch/nds32/lib/Makefile
@@ -29,12 +29,15 @@
 
 LIB	= $(obj)lib$(ARCH).o
 
-OBJS	:= board.o cache.o interrupts.o
+COBJS-y += board.o
+COBJS-y += cache.o
 COBJS-$(CONFIG_CMD_BOOTM) += bootm.o
+COBJS-y += interrupts.o
 
-all:	$(LIB)
+SRCS  := $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
 
-$(LIB):	$(OBJS) $(SOBJS)
+$(LIB): $(obj).depend $(OBJS)
 	$(call cmd_link_o_target, $(OBJS))
 
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