IntelSiliconPkg/IntelVTdPmrPei: Fix PMR enabling setting confilct

PMR enabling set by pre-boot DMA protection is cleared by RC
when boot guard is enabled. Pre-boot DMA protection should only
reset VT-d BAR when it is 0 and reset PMR region when it is
not programmed to protect all memory address.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2867



Change-Id: Ic5370f474a43a94903871782ace5cce186b4ddc0
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rangasai V Chaganty <rangasai.v.chaganty@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Jenny Huang <jenny.huang@intel.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>
Signed-off-by: Sheng Wei <w.sheng@intel.com>