[llvm] [AArch64] Set the default streaming hazard size to 1024 for +sme,+sve (PR #123753)

[Benjamin Maxwell via llvm-commits]

MacDue wrote:

I've set existing tests to `-aarch64-streaming-hazard-size=0` (to avoid churn). Let me know if you'd prefer for them to be regenerated. 

https://github.com/llvm/llvm-project/pull/123753