[MLIR] Apply clang-tidy fixes for llvm-prefer-isa-or-dyn-cast-in-conditionals in SimplifyAffineMinMax.cpp (NFC)

mlir/lib/Dialect/Affine/Transforms/SimplifyAffineMinMax.cpp

diff --git a/mlir/lib/Dialect/Affine/Transforms/SimplifyAffineMinMax.cpp b/mlir/lib/Dialect/Affine/Transforms/SimplifyAffineMinMax.cpp
index 2521512..f3e065a 100644
--- a/mlir/lib/Dialect/Affine/Transforms/SimplifyAffineMinMax.cpp
+++ b/mlir/lib/Dialect/Affine/Transforms/SimplifyAffineMinMax.cpp
@@ -151,10 +151,12 @@
                                                     bool *modified) {
   bool changed = false;
   for (Operation *op : ops) {
-    if (auto minOp = dyn_cast<AffineMinOp>(op))
+    if (auto minOp = dyn_cast<AffineMinOp>(op)) {
       changed = simplifyAffineMinOp(rewriter, minOp) || changed;
-    else if (auto maxOp = cast<AffineMaxOp>(op))
-      changed = simplifyAffineMaxOp(rewriter, maxOp) || changed;
+      continue;
+    }
+    auto maxOp = cast<AffineMaxOp>(op);
+    changed = simplifyAffineMaxOp(rewriter, maxOp) || changed;
   }
   RewritePatternSet patterns(rewriter.getContext());
   AffineMaxOp::getCanonicalizationPatterns(patterns, rewriter.getContext());