[X86] Add new #134979 test cases for gather scalar (#137416)
We are adding new test cases to see the transformation impact due to #134979.
These are similar to previous commit #688c3ffb057a87b86c6c1e77040418adf511efbb.
Handling struct with two member and different vector factor.
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Co-authored-by: Rohit Aggarwal <Rohit.Aggarwal@amd.com>