[llvm] [AArch64][SME] Disable tail-call optimization for __arm_locally_streaming functions. (PR #65258)

[via llvm-commits]

sdesmalen-arm wrote:

> > When calling e.g. a streaming-compatible function (which requires no streaming-mode change)
> 
> nit, commit message using e.g. implies there are other cases you know of but there's only one test case here

The other case would be where the callee would be an `__arm_streaming` function, which would have caused `CallerAttrs.requiresSMChange(CalleeAttrs)` to return `false`. I didn't think it was useful to add a test-case for this, because a call for `__arm_locally_streaming` -> `__arm_streaming_compatible` results in the same answer for `CallerAttrs.requiresSMChange(CalleeAttrs)`, and this interface is already tested extensively in another test.

https://github.com/llvm/llvm-project/pull/65258