[llvm] [VPlan] Expand VPWidenPointerInductionRecipe into separate recipes (PR #148274)

[Luke Lau via llvm-commits]

lukel97 wrote:

I've added a new VPInstruction::WidePtrAdd opcode to avoid changing VPInstruction::PtrAdd based on the review feedback here: https://github.com/llvm/llvm-project/pull/148273#pullrequestreview-3016425034

So this is no longer stacked on #148273 

https://github.com/llvm/llvm-project/pull/148274