[mlir][Linalg] Add a first vectorization pattern for conv1d in NWCxWCF format.

[mlir][Linalg] Add a first vectorization pattern for conv1d in NWCxWCF format.

This revision uses the newly refactored StructuredGenerator to create a simple vectorization for conv1d_nwc_wcf.

Note that the pattern is not specific to the op and is technically not even specific to the ConvolutionOpInterface (modulo minor details related to dilations and strides).

The overall design follows the same ideas as the lowering of vector::ContractionOp -> vector::OuterProduct: it seeks to be minimally complex, composable and extensible while avoiding inference analysis. Instead, we metaprogram the maps/indexings we expect and we match against them.

This is just a first stab and still needs to be evaluated for performance.
Other tradeoffs are possible that should be explored.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D111894