[clang] [flang] [Flang][Driver] Add -print-resource-dir command line flag to emit Flang's resource directory (PR #90886)

[Andrzej Warzyński via cfe-commits]

banach-space wrote:

> > What's the definition of "resource dir" for Fortran?
> 
> I'd like to at least have it point to where the MODULE files live.
> 
> When I look at what clang emits, then Flang's resource directory should rather point to the place, where Flang has its `lib` and `include` directories. So, one level above of what I have done in this PR right now.
> 

How does this compare to GFortran and Classic Flang? Anything resembling this flag?

https://github.com/llvm/llvm-project/pull/90886