avr32: Compile atmel_mci.o conditionally

Remove #ifdef CONFIG_MMC from the source file and use conditional
compilation in the Makefile instead.
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>

cpu/at32ap/Makefile

@@ -35,7 +35,7 @@ COBJS-y			+= exception.o
 COBJS-y			+= cache.o
 COBJS-y			+= interrupts.o
 COBJS-y			+= pio.o
-COBJS-y			+= atmel_mci.o
+COBJS-$(CONFIG_MMC)	+= atmel_mci.o
 
 SRCS	:= $(START-y:.o=.S) $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
 OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))

cpu/at32ap/atmel_mci.c

@@ -21,8 +21,6 @@
  */
 #include <common.h>
 
-#ifdef CONFIG_MMC
-
 #include <part.h>
 #include <mmc.h>
 
@@ -548,5 +546,3 @@ int mmc2info(ulong addr)
 {
 	return 0;
 }
-
-#endif /* CONFIG_MMC */