arch/x86: enable LOCALVERSION_AUTO config

Required to add revision of the git tree in kernel version.

Change-Id: Ib94d9eea64cd1f95ae415c204dac7e0035f3351f
Tracked-On: https://jira01.devtools.intel.com/browse/AW-6329


Signed-off-by: Victor Tasayco Loarte <victorx.tasayco.loarte@intel.com>
Reviewed-on: https://android.intel.com/597308


Reviewed-by: jenkins_ndg <jenkins_ndg@intel.com>
Reviewed-by: Korpershoek, MattijsX <mattijsx.korpershoek@intel.com>
Reviewed-by: Bertolin, PierreX <pierrex.bertolin@intel.com>