MdeModulePkg FirmwarePerfPei: Remove SEC performance data getting code

Current SEC performance data getting code in FirmwarePerformancePei
may get wrong SEC performance data if FirmwarePerformancePei executes
after memory discovered.

And as SecCore has added SecPerformancePpiCallBack to get SEC performance
data and build HOB to convey the SEC performance data to DXE phase.

This patch is to remove the SEC performance data getting code in
FirmwarePerformancePei.

Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>