WhiskeylakeOpenBoardPkg/WhiskeylakeURvp: Remove OpenBoardPkgConfig.dsc

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=2243



The location for PCD configuration is currently inconsistent in
WhiskeylakeOpenBoardPkg. A large set of FeaturePCD definitions are
in OpenBoardPkgConfig.dsc while other PCD definitions (including
FeaturePCD) are located in OpenBoardPkgPcd.dsc.

This change consolidates PCD configuration for the WhiskeylakeURvp
board to OpenBoardPkgPcd.dsc and removes OpenBoardPkgConfig.dsc.

Cc: Chasel Chiu <chasel.chiu@intel.com>
Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
Signed-off-by: Michael Kubacki <michael.a.kubacki@intel.com>
Reviewed-by: Chasel Chiu <chasel.chiu@intel.com>
Reviewed-by: Nate DeSimone <nathaniel.l.desimone@intel.com>