Adapt the rewriteAsPaddedOp method to use the OpBuilder instead of the PatterRewriter.
If paddingFunc returns failure we do not have a padding value. I agree the clean solution should be return failure in that case. But the exit condition will stay there. I will clean this up.
Turns out it is still needed. We use paddingFunc also to control if a specific operand shall be padded. So if there is no padding value this is actually not a failure but a success. We can refactor this once we use all the new flags / padding control.