[clang] [clang] Fix FnInfoOpts::operator&= and FnInfoOpts::operator|= not updating assigned operands (PR #107050)

[Eli Friedman via cfe-commits]

https://github.com/efriedma-quic approved this pull request.

LGTM... but in the future, please try to make the commit message indicate what effects this has.  (I'll rewrite it this time.)

https://github.com/llvm/llvm-project/pull/107050