[clang] [flang] [llvm] [openmp] [flang][driver] rename flang-new to flang (PR #110023)

[Kiran Chandramohan via cfe-commits]

kiranchandramohan wrote:

The 2 stage buildbot (https://lab.llvm.org/buildbot/#/builders/41) with the Fortran tests passed after this merge. Its latest run is also a pass.

https://github.com/llvm/llvm-project/pull/110023