[llvm] [GlobalISel][TableGen] Support for typed G_FCONSTANT Imm in MIR-patttern (PR #219563)

[Pierre van Houtryve via llvm-commits]

https://github.com/Pierre-vh approved this pull request.

I think this is fine for now and still an improvement.
Please wait at least 24h in case there are objections from other reviewers.

https://github.com/llvm/llvm-project/pull/219563