Don't use "-march=pentium3" for gcc tuning.

rth tells me that some versions of gcc may end up using the
SSE registers for data movement when you do that.

Use "-march=i686 -mtune=xxxx" instead.

(We do the same thing for march=pentium2/4 too, just for
consistency).

arch/i386/Makefile

@@ -32,17 +32,17 @@ cflags-$(CONFIG_M586)		+= -march=i586
 cflags-$(CONFIG_M586TSC)	+= -march=i586
 cflags-$(CONFIG_M586MMX)	+= $(call cc-option,-march=pentium-mmx,-march=i586)
 cflags-$(CONFIG_M686)		+= -march=i686
-cflags-$(CONFIG_MPENTIUMII)	+= $(call cc-option,-march=pentium2,-march=i686)
-cflags-$(CONFIG_MPENTIUMIII)	+= $(call cc-option,-march=pentium3,-march=i686)
-cflags-$(CONFIG_MPENTIUMM)	+= $(call cc-option,-march=pentium3,-march=i686)
-cflags-$(CONFIG_MPENTIUM4)	+= $(call cc-option,-march=pentium4,-march=i686)
+cflags-$(CONFIG_MPENTIUMII)	+= -march=i686 $(call cc-option,-mtune=pentium2)
+cflags-$(CONFIG_MPENTIUMIII)	+= -march=i686 $(call cc-option,-mtune=pentium3)
+cflags-$(CONFIG_MPENTIUMM)	+= -march=i686 $(call cc-option,-mtune=pentium3)
+cflags-$(CONFIG_MPENTIUM4)	+= -march=i686 $(call cc-option,-mtune=pentium4)
 cflags-$(CONFIG_MK6)		+= -march=k6
 # Please note, that patches that add -march=athlon-xp and friends are pointless.
 # They make zero difference whatsosever to performance at this time.
 cflags-$(CONFIG_MK7)		+= $(call cc-option,-march=athlon,-march=i686 $(align)-functions=4)
 cflags-$(CONFIG_MK8)		+= $(call cc-option,-march=k8,$(call cc-option,-march=athlon,-march=i686 $(align)-functions=4))
 cflags-$(CONFIG_MCRUSOE)	+= -march=i686 $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
-cflags-$(CONFIG_MEFFICEON)	+= $(call cc-option,-march=pentium3,-march=i686) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
+cflags-$(CONFIG_MEFFICEON)	+= -march=i686 $(call cc-option,-mtune=pentium3) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
 cflags-$(CONFIG_MWINCHIPC6)	+= $(call cc-option,-march=winchip-c6,-march=i586)
 cflags-$(CONFIG_MWINCHIP2)	+= $(call cc-option,-march=winchip2,-march=i586)
 cflags-$(CONFIG_MWINCHIP3D)	+= $(call cc-option,-march=winchip2,-march=i586)