Set TARGET_CPUS on x86_64 to cpu_online_map.  This brings the code inline
with x86 mach-default.  Fix MSI_TARGET_CPU code which will break with this
target_cpus change.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>