[tosa] Support legalization of tfl.gather with multiple dynamic dimensions
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For the most up to date status, view the checks section at the bottom of the pull request. Hi @sabauma Can you please resolve conflicts? Thank you! I think I've resolved all the existing issues. Just waiting for @rsuderman to give another pass. The changes that were originally in this PR now appear in the upstream repo on the master branch. I'm not sure what is going on, as this PR was never accepted. This PR now appears to be mostly empty due to all the changes being moved upstream.

@gbaned would you have some insight into what is going on? Hi @rsuderman Can you please assist on above comments from @sabauma. Thank you! Hi @rsuderman Any update on this PR? Please. Thank you! Hi @rsuderman Any update on this PR? Please. Thank you! Hi @rsuderman Any update on this PR? Please. Thank you! Hi @rsuderman Any update on this PR? Please. Thank you! Hi @rdzhabarov Can you please assist on above [comments](https://github.com/tensorflow/tensorflow/pull/61368#issuecomment-1669593469) from @sabauma. Thank you!


The existing lowering of tfl.gather targets a sequence of tosa.reshape and tosa.gather operations. Currently, tosa.reshape supports, at most, a single dynamic dimension. This change adds support for multiple dynamic dimensions by targeting the tensor.reshape operator in the presence of multiple dynamic dimensions.