[llvm] [DecoderEmitter] Support for DecodeOrder and `resolve-conflicts-try-all` (PR #157948)

[Rahul Joshi via llvm-commits]

jurahul wrote:

With the latest version, the AArch64 issue is fixed (SoftFail handling subtleties, it seems for the purpose of decoding SoftFail is like a Success and not a failure). Also, I had to introduce 2 scope stacks. 

https://github.com/llvm/llvm-project/pull/157948