MdeModulePkg/ReportStatusCodeRouter: Clear RSC Data buffer if Data is NULL

MdeModulePkg/ReportStatusCodeRouter: Clear RSC Data buffer if Data is NULL

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=1969

ReportDispatcher() may be invoked with a NULL Data argument. When TPL is
less than TPL_HIGH_LEVEL and Data is NULL, the EFI_STATUS_CODE_DATA
structure inside RscData should be cleared so listeners will not receive
data from a previous operation.

Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Kun Qin <Kun.Qin@microsoft.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Dandan Bi <dandan.bi@intel.com>