x86_64: TargetReg update for x86

Also includes changes in common code. Elimination of use of TargetReg
with one parameter and direct access to special target registers.

Change-Id: Ied2c1f87d4d1e4345248afe74bca40487a46a371
Signed-off-by: Serguei Katkov <serguei.i.katkov@intel.com>
Signed-off-by: Chao-ying Fu <chao-ying.fu@intel.com>
14 files changed