[MLIR] Add missing forward declaration after 61d5fdf (#141734)

Author: WillFroom

mlir/include/mlir/Dialect/Bufferization/Transforms/Bufferize.h

@@ -26,6 +26,7 @@ namespace bufferization {
 
 class AnalysisState;
 struct BufferizationOptions;
+class BufferizationState;
 class OpFilter;
 
 /// Bufferization statistics for debugging. These can be printed after running