Make helpers static. Add missing include so LLVMInitializeObjCARCOpts gets C linkage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175264 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/SourceMgr.cpp b/lib/Support/SourceMgr.cpp
index fa82265..fac3cad 100644
--- a/lib/Support/SourceMgr.cpp
+++ b/lib/Support/SourceMgr.cpp
@@ -248,8 +248,8 @@
   std::sort(FixIts.begin(), FixIts.end());
 }
 
-void buildFixItLine(std::string &CaretLine, std::string &FixItLine,
-                    ArrayRef<SMFixIt> FixIts, ArrayRef<char> SourceLine) {
+static void buildFixItLine(std::string &CaretLine, std::string &FixItLine,
+                           ArrayRef<SMFixIt> FixIts, ArrayRef<char> SourceLine){
   if (FixIts.empty())
     return;