Previously it was only run for Intel CPUs, but AMD Fam10h implements MWAIT too.

This matches 64bit behaviour.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>