[llvm] [AArch64] Prevent argument promotion of vector with size > 128 bits (PR #70034)

[Paul Walker via llvm-commits]

https://github.com/paulwalker-arm commented:

Thanks for the fix.  I've one comment but otherwise this looks good.  I'll try to find some time in the run up to LLVM 18 to see if the underlying code generation issue can be resolved.

https://github.com/llvm/llvm-project/pull/70034