[clang] [clang][ssaf][NFC] Move SSAF flags from FrontendOptions to a dedicated SSAFOptions (PR #204621)

[Jordan Rupprecht via cfe-commits]

rupprecht wrote:

This introduced a [layering violation](https://llvm.org/docs/CodingStandards.html#library-layering) between Frontend and ScalableStaticAnalysisFramework/Frontend. I suspect that's related to the link failure on windows.

https://github.com/llvm/llvm-project/pull/204621