[clang] [PAC][clang][Driver] Add signed GOT flag (PR #96160)

[Daniil Kovalev via cfe-commits]

kovdan01 wrote:

@MaskRay @ahmedbougacha @asl I suggest to move the discussion on comma-separated flags/current flags to an issue #97320. This PR is intended to introduce the signed GOT flag, and we already have a bunch of similar ptrauth flags, so, if we want to change the flags to a single comma-separated value, we need to do that as a separate refactoring PR but not here. As for this PR, I suggest to stick with old convention not to make this a blocker.

@MaskRay please let me know if you have other issues with proposed changes except suggestion to use comma-separated flags.

https://github.com/llvm/llvm-project/pull/96160