[clang] [clang] odr-checker fix for conversion operators (PR #146153)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

> Thanks! I don't know if similar problems (ODR confused by the canonicalization merging decltypes with different names of template parameters) can show up in other cases, but as the PR fixes this particular case LGTM.

Sure, please file bug reports for any other similar cases this patch does not fix.

https://github.com/llvm/llvm-project/pull/146153