make the 'to match this' diagnostic a note.

llvm-svn: 59921
diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp
index 221ad90..7006241 100644
--- a/clang/lib/Parse/ParseStmt.cpp
+++ b/clang/lib/Parse/ParseStmt.cpp
@@ -733,7 +733,7 @@
     ExitScope();
     if (!Body.isInvalid) {
       Diag(Tok, diag::err_expected_while);
-      Diag(DoLoc, diag::err_matching) << "do";
+      Diag(DoLoc, diag::note_matching) << "do";
       SkipUntil(tok::semi, false, true);
     }
     return true;