[PATCH] re-enable -mabi=no-altivec, use -mabi=altivec as default for powerpc-linux

[David Edelsohn]

Janis,

	I am worried about the changes to the handling of VRSAVE.

	First, the patch changes TARGET_ALTIVEC_VRSAVE so that it always
is enabled for TARGET_ELF.  It only should be enabled when
rs6000_altivec_abi is enabled.

	Second, PPC32 Linux never seems to have enabled
TARGET_ALTIVEC_VRSAVE automatically.  The Altivec PIM implies that it is
suppose to be set for SVR4.  What is the status of VRSAVE in the PPC32
Linux ABI?

Thanks, David