Revert "[mlir][linalg] Decompose winograd operators"

This reverts commit 24c4f95.

Author: Hsiangkai

mlir/include/mlir/Dialect/Linalg/Transforms/Transforms.h

@@ -1703,9 +1703,6 @@ void populateBlockPackMatmulPatterns(RewritePatternSet &patterns,
 void populateWinogradConv2DPatterns(RewritePatternSet &patterns, int64_t m,
                                     int64_t r);
 
-/// Patterns to decompose Winograd operators.
-void populateDecomposeWinogradOpsPatterns(RewritePatternSet &patterns);
-
 } // namespace linalg
 } // namespace mlir