[clang] [llvm] [llvm][DebugInfo][clang] Finalize all declaration subprograms in DIBuilder::finalize() (PR #139914)

[David Blaikie via cfe-commits]

dwblaikie wrote:

yeah, can't say I have any recollection of why function declaration would be in a "retained types" list - probably incidental/not especially intentional (we didn't make declarations for functions, except member functions, until "recently" when call site debug info was added). I guess it's worth a go to add them to all the subprograms.

https://github.com/llvm/llvm-project/pull/139914