Tidy-up AROPTS for cpu native

arch/cpu/native/Makefile.native

@@ -20,7 +20,7 @@ CFLAGSNO = -Wall -g -I/usr/local/include $(CFLAGSWERROR)
 CFLAGS  += $(CFLAGSNO)
 
 ifeq ($(HOST_OS),Darwin)
-AROPTS = -r
+AROPTS = -rc
 LDFLAGS += -Wl,-flat_namespace,-map,$(CONTIKI_NG_PROJECT_MAP)
 CFLAGS += -DHAVE_SNPRINTF=1 -U__ASSERT_USE_STDERR
 else

arch/platform/native/Makefile.native

@@ -2,9 +2,6 @@ ifndef CONTIKI
   $(error CONTIKI not defined! You must specify where CONTIKI resides!)
 endif
 
-ifeq ($(HOST_OS),Darwin)
-  AROPTS = rc
-endif
 
 CONTIKI_TARGET_DIRS = . dev
 CONTIKI_TARGET_MAIN = ${addprefix $(OBJECTDIR)/,contiki-main.o}