[clang] [llvm] Revert "[AArch64] Add soft-float ABI (#74460)" (PR #82032)

[Nathan Chancellor via cfe-commits]

nathanchance wrote:

This does not appear to drop `clang/test/Driver/aarch64-soft-float-abi.c` which was added by that change, do the tests pass with that test still present? I am guessing there was a conflict because of the forward fix in 5b8e7ed787f6e537876c4fdafd070eba9681f343.

Regardless, I approve of a revert if there is no quick forward fix, our continuous integration is quite red because of this.

https://github.com/llvm/llvm-project/pull/82032