TorchToTosa: attempt to fold tosa::add in AtenBroadcastToOp legalization.

[ttjost]

No description provided.

[mgehre-amd]

Curious, why was this change necessary for your story? Or is this a drive-by fix?

[ttjost]

Curious, why was this change necessary for your story? Or is this a drive-by fix?

For the model we are testing, repeat.interleave uses the broadcast_to operation as the repeat operand of the operation. It turns out that we cannot work with the add created by the broadcast_tolegalization, but the operation can be folded to a constant. It is only then that we are able to legalizerepeat_interleave. Unfortunately, I don't think we can go much further than that for the repeat_interleave` story, meaning, things have to be constant foldable.