[MLIR] Fix iteration counting in greedy pattern application

Previously, checking that a fix point is reached was counted as a full
iteration. As this "iteration" never changes the IR, this seems counter-
intuitive.

Differential Revision: https://reviews.llvm.org/D123641

mlir/lib/Transforms/Utils/GreedyPatternRewriteDriver.cpp

@@ -274,7 +274,7 @@ bool GreedyPatternRewriteDriver::simplify(MutableArrayRef<Region> regions) {
     if (config.enableRegionSimplification)
       changed |= succeeded(simplifyRegions(*this, regions));
   } while (changed &&
-           (++iteration < config.maxIterations ||
+           (iteration++ < config.maxIterations ||
             config.maxIterations == GreedyRewriteConfig::kNoIterationLimit));
 
   // Whether the rewrite converges, i.e. wasn't changed in the last iteration.