CodeGen, Driver: Add -fsanitize-trap-loop option.
This option may be used to opt into infinite loops for failed UBSan and
CFI checks. It causes Clang to generate an llvm.cond.loop intrinsic call
instead of a conditional branch to a trap instruction when generating
code for a conditional trap.
Part of this RFC:
https://discourse.llvm.org/t/rfc-optimizing-conditional-traps/89456
Reviewers: fmayer, vitalybuka
Reviewed By: vitalybuka, fmayer
Pull Request: https://github.com/llvm/llvm-project/pull/177688
