Add the .td description for evalOp

[zmbekdemir]

Tried to add the structure for polynomial.eval op. This does not give error during compiling but not sure this is the final structure and I would appreciate some insights and recommendations for the roadmap. #1217

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[j2kun]

Hello! I'll take a look after breakfast and send some feedback.

[zmbekdemir]

Hello :) I have realized that I was working directly on main and therefore closed this pr to open a new one. They have the same thing but I just thought it is best to work on a branch. Open one is this #1271 . Enjoy your breakfast.