[llvm] [CodeGen][GC] Remove `GCInfoPrinter` (PR #75033)

[via llvm-commits]

paperchalice wrote:

> Can you expand the statement "This pass is broken and looks like no one uses it." ? I suspect that it is broken due to the following inverted condition
> 
> ```
> bool Printer::runOnFunction(Function &F) {
>   if (F.hasGC()) ///////
>     return false;
> ```

This code triggers the assertion:
https://github.com/llvm/llvm-project/blob/2e197602305be18b963928e6ae024a004a95af6d/llvm/lib/CodeGen/GCMetadata.cpp#L64-L66
No one has noticed it for the last 15 years.

https://github.com/llvm/llvm-project/pull/75033