MinPlatformPkg/TestPointCheckLib: Prevent modification of HOB data

DumpMemoryTypeInfoSummary() is used to dump information about the
MemoryTypeInformation HOB. The dump function currently modifies the
data which can corrupt the data for later HOB consumers in the DXE
phase.

This change makes DumpMemoryTypeInfoSummary() treat the data as
read-only.

Cc: Chasel Chiu <chasel.chiu@intel.com>
Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
Cc: Isaac Oram <isaac.w.oram@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Eric Dong <eric.dong@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Isaac Oram <isaac.w.oram@intel.com>