Fix warnings detected by -Wpessimizing-move

patch by Eugene Zelenko

Differential Revision: http://reviews.llvm.org/D11429

llvm-svn: 243399
diff --git a/lldb/source/Expression/ClangExpressionParser.cpp b/lldb/source/Expression/ClangExpressionParser.cpp
index 2b344b0c..d59e8e0 100644
--- a/lldb/source/Expression/ClangExpressionParser.cpp
+++ b/lldb/source/Expression/ClangExpressionParser.cpp
@@ -372,7 +372,7 @@
         if (HostInfo::GetLLDBPath(lldb::ePathTypeLLDBTempSystemDir, tmpdir_file_spec))
         {
             tmpdir_file_spec.AppendPathComponent("lldb-%%%%%%.expr");
-            temp_source_path = std::move(tmpdir_file_spec.GetPath());
+            temp_source_path = tmpdir_file_spec.GetPath();
             llvm::sys::fs::createUniqueFile(temp_source_path, temp_fd, result_path);
         }
         else