[llvm] [VPlan] Don't convert VPWidenSelectRecipes to vp.select in EVL transform (PR #146695)

[Luke Lau via llvm-commits]

lukel97 wrote:

> We only iterate through the users of the headermask calling createEVLRecipe.

This bit tripped me up when I was looking at https://github.com/llvm/llvm-project/pull/146672, but we iterate recursively through the users IIUC. So a select may not use the header mask directly, but another recipe that used the header mask. 

https://github.com/llvm/llvm-project/pull/146695