[PATCH] x86_64: Quieten down microcode update driver

Only log data in microcode driver when something is changed Otherwise it
was far too noisy on large systems.

Also remove the printk when it is unloaded.

Cc: tigran@veritas.com

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>