[llvm] [ARM] Have the subtraction of a large number be turned into the addition of its negative in TableGen (PR #196866)

[via llvm-commits]

LumioseSil wrote:

@john-brawn-arm ignore the one where there was a 3 instruction increase that's a result of sp management and as of now I don't know how to fix.

https://github.com/llvm/llvm-project/pull/196866