[Polly] Remove pipeline-level Oz handling for LoopRotate (#191137)

This handling was moved fully into the pass in
1662c200a5b151ad15b7efc82837076d8967dc11. However, that changed
missed the usage of LoopRotate in polly.

GitOrigin-RevId: 3ad6afe0609b2138b81f773cf4fbe2d464bc26d6
1 file changed