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

Implementation of early update ucode on Intel's CPU.

load_ucode_intel_bsp() scans ucode in initrd image file which is a cpio format
ucode followed by ordinary initrd image file. The binary ucode file is stored
in kernel/x86/microcode/GenuineIntel.bin in the cpio data. All ucode
patches with the same model as BSP are saved in memory. A matching ucode patch
is updated on BSP.

load_ucode_intel_ap() reads saved ucoded patches and updates ucode on AP.

Signed-off-by: Fenghua Yu <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>