Clean up an overlong line in arch/x86/kernel/cpu/amd_64.c.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Create a separate amd_64.c file in the cpu/ dir for
the useful parts to live in.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>