[mlir][linalg] Remove padding from tiling options.

Remove the padding options from the tiling options since padding is now implemented by a separate pattern/pass introduced in https://reviews.llvm.org/D112412.

The revsion remove the tile-and-pad-tensors.mlir and replaces it with the pad.mlir that tests padding in isolation (without tiling). Similarly, hoist-padding.mlir is replaced by pad-and-hoist.mlir introduced in https://reviews.llvm.org/D112713.

Depends On D112838

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D113382