x86: code split to two parts

Split off existing code into two seperate files. One file holds general
code, the other file vendor specific parts.

No functional changes, only refactoring.

Temporarily Introduced a new module name 'ucode' for result,
due to already taken name 'microcode'.

Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>