[llvm] [AArch64] Adjust cost for min/max intrinsics using v2i8 and v2i16 (PR #212801)

[Jack Styles via llvm-commits]

Stylie777 wrote:

I've opened https://github.com/llvm/llvm-project/pull/212966 to handle min/max intrinsics and widen these types instead. 

This PR was made in reaction to a comment in https://github.com/llvm/llvm-project/pull/195823 to stop vectorisation of certain examples where vectorisation was not profitable. I have probably inadvertently overcosted in this case to get it to stop vectorisation.

https://github.com/llvm/llvm-project/pull/212801