[llvm] [RISCV][VLOPT] Enable the RISCVVLOptimizer by default (PR #119461)

[Luke Lau via llvm-commits]

lukel97 wrote:

> > Have you had a chance to kick the tires with this on llvm-test-suite or SPEC?
> 
> I had a chance to run this on spec2006/int/train and spec2017/int/train on qemu. Both build and terminate without errors.

Nice, this also just came to mind but did you run it with the `rvv_ta_all_1s=1` option set? I'm thinking if there were any potential miscompiles then this would probably be needed to catch them

https://github.com/llvm/llvm-project/pull/119461