Current GenFds Tool class GuidSection() is parsing the tools_def.txt for
every GUID'ed section that has a GUID defined tool, it cause a bad
performance. so this patch cache the defined Guid tool to improve the
performance.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Yonghong Zhu <yonghong.zhu@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>