MdeModulePkg/ReportStatusCodeLib: Avoid using AllocatePool if possible

MdeModulePkg/ReportStatusCodeLib: Avoid using AllocatePool if possible

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1114

V2: simplify the code logic.
update
if (!mHaveExitedBootServices &&
  (StatusCodeData != (EFI_STATUS_CODE_DATA *) StatusCodeBuffer)) {
  gBS->FreePool (StatusCodeData);
}
to
if (StatusCodeData != (EFI_STATUS_CODE_DATA *) StatusCodeBuffer) {
  gBS->FreePool (StatusCodeData);
}

V3:
And the code below into the else condition (stack buffer is not enough)
in /DxeReportStatusCodeLib/ReportStatusCodeLib.c

  if (gBS == NULL || gBS->AllocatePool == NULL || gBS->FreePool == NULL) {
    return EFI_UNSUPPORTED;
  }

V4:
Refine code logic.

When report status code with ExtendedData data,
and the extended data can fit in the local static buffer,
there is no need to use AllocatePool to hold the ExtendedData data.

This patch is just to do the enhancement to avoid using AllocatePool.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Cc: Michael Turner <Michael.Turner@microsoft.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>