[SelectionDAG] Fix missing lambda capture

Move MaxDepth into the lambda, since it is not needed outside. This
fixes some compilers that complain about missing capture:

  error C3493: 'MaxDepth' cannot be implicitly captured because no
  default capture mode has been specified

Fixes: f693932 ("[SelectionDAG] Transitively copy NodeExtraInfo on RAUW")

Author: melver

llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

@@ -12240,8 +12240,8 @@ void SelectionDAG::copyExtraInfo(SDNode *From, SDNode *To) {
   // from the old From node. This avoids copying NodeExtraInfo to parts of the
   // DAG that is not new and should be left untouched.
   DenseSet<const SDNode *> Visited;
-  constexpr int MaxDepth = 16;
   auto VisitFrom = [&Visited](auto &&Self, SDNode *N, int Depth) {
+    constexpr int MaxDepth = 16;
     if (Depth >= MaxDepth)
       return;
     if (!Visited.insert(N).second)