[PATCH] x86/smpboot: check if CLFLUSH is actually necessary

[Scotty Bauer]

This is a multi-part message in MIME format.mwait_play_dead previously issued a CLFLUSH to work around a bug on some xeon processors. We can now determine if the CPU is a buggy CPU. This patch checks if if we're on a buggy CPU which allows non-buggy cpu's to eliminate the CLFLUSH.