[llvm] [AArch64][SME] Only use ADDSVL for SVE stack if there's a streaming body (PR #152323)

[Sander de Smalen via llvm-commits]

https://github.com/sdesmalen-arm requested changes to this pull request.

We discussed this offline; SVE locals that have their address passed to a function, even if that call (or any other part of the function) doesn't require a streaming mode change, should still be allocated with `addsvl`.

https://github.com/llvm/llvm-project/pull/152323