[flang-commits] [flang] [flang] Warn when F128 is unsupported (#102147) (PR #106957)

[Tom Eccles via flang-commits]

tblah wrote:

@vzakhari are you happy with this with the TODO message added in [67b1f42](https://github.com/llvm/llvm-project/pull/106957/commits/67b1f42b7d70a0e19d9ac0390cb9a7ef5804080a)?

https://github.com/llvm/llvm-project/pull/106957