ia64: Re-enable -frename-registers for McKinley.

arch/ia64/Makefile

@@ -19,7 +19,7 @@ AFLAGS_KERNEL	:= -mconstant-gp
 EXTRA		:=
 
 cflags-y	:= -pipe $(EXTRA) -ffixed-r13 -mfixed-range=f10-f15,f32-f127 \
-		   -falign-functions=32
+		   -falign-functions=32 -frename-registers
 CFLAGS_KERNEL	:= -mconstant-gp
 
 GCC_VERSION=$(shell $(CC) -v 2>&1 | fgrep 'gcc version' | cut -f3 -d' ' | cut -f1 -d'.')
@@ -37,8 +37,6 @@ endif
 
 ifeq ($(GCC_VERSION),2)
 $(error Sorry, your compiler is too old.  GCC v2.96 is known to generate bad code.)
-else
-cflags-$(CONFIG_ITANIUM)	+= -frename-registers
 endif
 
 ifeq ($(GCC_VERSION),3)