Fix builds that use an stl missing std::set::emplace

llvm-svn: 206821
diff --git a/llvm/utils/TableGen/DFAPacketizerEmitter.cpp b/llvm/utils/TableGen/DFAPacketizerEmitter.cpp
index e5a6bb6..8a2fb32 100644
--- a/llvm/utils/TableGen/DFAPacketizerEmitter.cpp
+++ b/llvm/utils/TableGen/DFAPacketizerEmitter.cpp
@@ -245,7 +245,7 @@
 
 
 const State &DFA::newState() {
-  auto IterPair = states.emplace();
+  auto IterPair = states.insert(State());
   assert(IterPair.second && "State already exists");
   return *IterPair.first;
 }