[TOSA] bug fix convert-tfl-uint8 and TFL Cast legalization
reworked per review comment, and rebased. Hi @Tai78641 Can you please resolve conflicts? Thank you! > Hi @Tai78641 Can you please resolve conflicts? Thank you!

resolved merge conflicts resolved merge conflicts Hi @Tai78641 Can you please resolve conflicts? Thank you! rebased to resolve conflicts Hi @rsuderman, Can you please review this PR ? Thank you! Hi @jpienaar, Can you please review this PR ? Thank you! Hi @jpienaar, Can you please review this PR ? Thank you! Hi @jpienaar, Can you please review this PR ? Thank you! Hi @jpienaar, Can you please review this PR ? Thank you! @NatashaKnk would you review this please? Hi @Tai78641 Can you please resolve conflicts? Thank you! > Hi @Tai78641 Can you please resolve conflicts? Thank you!

rebased and resolved conflicts Hi @NatashaKnk Can you please review this PR? Thank you! Hi @NatashaKnk Can you please review this PR? Thank you!
1. refactor convert-tfl-uint8 transform and applies the ui8 fix to rest of the transform (instead of only to the bb arg tensors)
2. fix tfl.cast legalization to take care of when input types have non-0 zero points
3. fix tfl.argmin legalization for input/output types with non-0 zero points
4. add tests and checks for above cast/argmin for ui8 and non-zero quantized type
