[llvm] [AArch64][CostModel] Lower cost of dupq (SVE2.1) (PR #144918)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

The scores look OK to me. A couple of other suggestions but looks good otherwise, if @sdesmalen-arm is happy.

https://github.com/llvm/llvm-project/pull/144918