UefiCpuPkg/CpuS3DataDxe: Consume the existing PcdCpuS3DataAddress

UefiCpuPkg/CpuS3DataDxe: Consume the existing PcdCpuS3DataAddress

If PCD PcdCpuS3DataAddress is set before, CpuS3DataDxe should get RegisterTable
and PreSmmRegisterTable from existing PCD pointed buffer and needn't to allocate
new buffer for RegisterTable and PreSmmRegisterTable.

Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>