[llvm] [LV] Add VPWiden{Load|Store}EVLRecipe into emitInvalidCostRemarks(). (PR #119708)

[Florian Hahn via llvm-commits]

fhahn wrote:

> > Tests?
> 
> It hard to find a test case that using VPWidenLoadEVL and the cost is invalid. Something I can imagine is that gather/scatter under `--triple riscv64 -mattr=+v` will return invalid cost. However, this pattern will not be vectorized in the upstream compiler.

If the assumption is we cannot encounter those, could it be an assert instead? Not sure if the type switch would already assert.

https://github.com/llvm/llvm-project/pull/119708