x86, AMD: Clean up init_amd()

Clean up multiple declarations of variable used for rd/wrmsr.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com>
Link: http://lkml.kernel.org/r/1359495136-23244-1-git-send-email-ostr@amd64.org


Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>