WhitleyOpenBoardPkg/Build: Enable includable build options
Separate the [BuildOptions] sections of the DSC to facilitate
multiple DSC builds for prebuilding.
Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
Cc: Chasel Chiu <chasel.chiu@intel.com>
Signed-off-by: Isaac Oram <isaac.w.oram@intel.com>
Reviewed-by: Nate DeSimone <nathaniel.l.desimone@intel.com>