UefiCpuPkg: Update default for PcdCpuProcTraceMemSize/PcdCpuProcTraceOutputScheme.

UefiCpuPkg: Update default for PcdCpuProcTraceMemSize/PcdCpuProcTraceOutputScheme.

These two definitions have redundant definition which can be handle by code.
This patch update them to follow new code definitions.

V2: Add more comments for the PCDs and keep consistent in .dec and .uni files.

Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>