Move "ar" flags to config.mk to allow for silent "make -s"
Based on patch by Mike Frysinger, 20 Jun 2006
diff --git a/cpu/74xx_7xx/Makefile b/cpu/74xx_7xx/Makefile
index e82fffc..fe905f3 100644
--- a/cpu/74xx_7xx/Makefile
+++ b/cpu/74xx_7xx/Makefile
@@ -39,7 +39,7 @@
 all:	$(obj).depend $(START) $(LIB)
 
 $(LIB):	$(OBJS)
-	$(AR) crv $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 
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