Replace uses of the deprecated std::auto_ptr with OwningPtr.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179373 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-ranlib/llvm-ranlib.cpp b/tools/llvm-ranlib/llvm-ranlib.cpp
index fe9d3e2..e3e3bad 100644
--- a/tools/llvm-ranlib/llvm-ranlib.cpp
+++ b/tools/llvm-ranlib/llvm-ranlib.cpp
@@ -78,7 +78,7 @@
   }
 
   std::string err_msg;
-  std::auto_ptr<Archive>
+  OwningPtr<Archive>
     AutoArchive(Archive::OpenAndLoad(ArchivePath, Context, &err_msg));
   Archive* TheArchive = AutoArchive.get();
   if (!TheArchive) {