avr32: Use new-style Makefile for the at32ap platform
This makes it easier to avoid compiling certain files later.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
diff --git a/cpu/at32ap/Makefile b/cpu/at32ap/Makefile
index f69b1f3..8e384c7 100644
--- a/cpu/at32ap/Makefile
+++ b/cpu/at32ap/Makefile
@@ -27,13 +27,20 @@
LIB := $(obj)lib$(CPU).a
-START := start.o
-SOBJS := entry.o
-COBJS := cpu.o hsdramc.o exception.o cache.o
-COBJS += interrupts.o pio.o atmel_mci.o
-SRCS := $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
-OBJS := $(addprefix $(obj),$(SOBJS) $(COBJS))
-START := $(addprefix $(obj),$(START))
+START-y += start.o
+
+SOBJS-y += entry.o
+COBJS-y += cpu.o
+COBJS-y += hsdramc.o
+COBJS-y += exception.o
+COBJS-y += cache.o
+COBJS-y += interrupts.o
+COBJS-y += pio.o
+COBJS-y += atmel_mci.o
+
+SRCS := $(START-y:.o=.S) $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
+OBJS := $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
+START := $(addprefix $(obj),$(START-y))
all: $(obj).depend $(START) $(LIB)