Update tosa.mul op in StableHLO-to-TOSA Pass in compliance with MLIR upstream and TOSA-v1.0

[bubblepipe]

This PR updates the StableHLO to TOSA legalization pass to align with the recent changes in the MLIR upstream. Specifically, the tosa::MulOp operation has being modified to comply with the TOSA-v1.0 specification. The shift parameter of the MUL operator, which was previously an attribute, has been moved to an SSA operand. 

The upstream changes caused a compilation failure in the StableHLO to TOSA conversion pass because the tosa.mul operation now expects 3 operand groups instead of 2, as reflected in the error message:

error: invalid number of operand groups for `tosa.mul`; expected 3, but got 2
     with op<tosa.mul>(input0, input1) {shift = attr<"0 : i8">};
          ^

This PR added a zero constant as the additional argument for the shift parameter to maintain compatibility with the updated tosa.mul operation.

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[GleasonK]

Thank you for the fix! We are still integrating these TOSA / LLVM changes throughout the rest of the OpenXLA projects, we will merge this change as a part of our next LLVM bump and ensure you are attributed as author of the fix