Revert "R600: Use SchedModel enum for is{Trans,Vector}Only functions"

This reverts commit 3f1de26cb5cc0543a6a1d71259a7a39d97139051.
Revert "TableGen: Enumerate Schedule Model too."

This reverts commit 2ca1e4a39c7e0d7a00e66ff5437c6d7ace2404a0.