x86/microcode_intel_lib.c: Early update ucode on Intel's CPU

Define interfaces microcode_sanity_check() and get_matching_microcode(). They
are called both in early boot time and in microcode Intel driver.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1356075872-3054-7-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>