powerpc: Makefile simplification through use of cc-ifversion

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/Makefile

@@ -77,7 +77,7 @@ CPP		= $(CC) -E $(KBUILD_CFLAGS)
 CHECKFLAGS	+= -m$(CONFIG_WORD_SIZE) -D__powerpc__ -D__powerpc$(CONFIG_WORD_SIZE)__
 
 ifeq ($(CONFIG_PPC64),y)
-GCC_BROKEN_VEC	:= $(shell if [ $(call cc-version) -lt 0400 ] ; then echo "y"; fi)
+GCC_BROKEN_VEC	:= $(call cc-ifversion, -lt, 0400, y)
 
 ifeq ($(CONFIG_POWER4_ONLY),y)
 ifeq ($(CONFIG_ALTIVEC),y)