CET for Exception Handle

Summary:
Bug fix for https://bugs.llvm.org/show_bug.cgi?id=45182
Exception handle may indirectly jump to catch pad, So we should add ENDBR instruction before catch pad instructions.

Reviewers: craig.topper, hjl.tools, LuoYuanke, annita.zhang, pengfei

Reviewed By: LuoYuanke

Subscribers: hiraditya, llvm-commits

Patch By: Xiang Zhang (xiangzhangllvm)

Differential Revision: https://reviews.llvm.org/D76190