x86/mce: Don't use percpu workqueues

x86/mce: Don't use percpu workqueues

An MCE is a rare event. Therefore, there's no need to have
per-CPU instances of both normal and IRQ workqueues. Make them
both global.

Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
[ Fold in subsequent patch from Rui/Boris/Tony for early boot logging. ]
Signed-off-by: Tony Luck <tony.luck@intel.com>
[ Massage commit message. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1439396985-12812-4-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>