[clang] [flang][driver] support -dumpversion and -dumpmachine (PR #68896)

[Yuanfang Chen via cfe-commits]

yuanfang-chen wrote:

> You are adding a support for these new flags in `flang-new`, which is implemented in terms of `clangDriver` - this scenario (i.e. the two projects being out of sync) would be very unlikely at the moment (perhaps even impossible). And even if that was desired, you'd need to update Flang's driver too. I'd rather keep this to the required minimum. If you really want to keep this, you will need to update flang/tools/flang-driver/driver.cpp too.

Thanks for the explanation. I've updated the patch.

https://github.com/llvm/llvm-project/pull/68896