[llvm] [AArch64] Change IssueWidth to 6 in AArch64SchedNeoverseV2.td (PR #142565)

[Sjoerd Meijer via llvm-commits]

sjoerdmeijer wrote:

Hi David, I think this makes sense. I would like to run some more benchmarks, and will report back here in a day or two. 

https://github.com/llvm/llvm-project/pull/142565