[llvm] [HEXAGON] Add AssertSext in sign-extended mpy (PR #149061)

[Sudharsan Veeravalli via llvm-commits]

https://github.com/svs-quic approved this pull request.

LGTM! The co-authored line needs to include the email id of the co-author as well.  If one isn't available then I would suggest just removing it.

Please refer to https://docs.github.com/en/pull-requests/committing-changes-to-your-project/creating-and-editing-commits/creating-a-commit-with-multiple-authors

https://github.com/llvm/llvm-project/pull/149061