SimicsOpenBoardPkg/BoardX58Ich10: DSC cleanup

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=2244



This change refactors OpenBoardPkg.dsc and OpenBoardPkgPcd.dsc to
consolidate redundant sections and better group file content to
improve maintainability and readability.

The same pattern made in this change for BoardX58Ich10 is being
applied to all existing board packages in Platform/Intel to improve
overall consistency.

Cc: Agyeman Prince <prince.agyeman@intel.com>
Cc: Wei David Y <david.y.wei@intel.com>
Signed-off-by: Michael Kubacki <michael.a.kubacki@intel.com>
Reviewed-by: Prince Agyeman <prince.agyeman@intel.com>
Reviewed-by: Nate DeSimone <nathaniel.l.desimone@intel.com>