[VPlan] Make sure optimizeInductions removes wide ind from scalar plan.

In some cases, there may be widened users of inductions even though the
plan includes the scalar VF. In those cases, make sure we still replace
the VPWidenIntOrFpInductionRecipe with scalar steps, as otherwise we may
try to execute a VPWidenIntOrFpInductionRecipe with a scalar VF.

Alternatively the patch could also split the range if needed.

This fixes a crash exposed by D123720.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D128755