Fix missing 'clang' in pragma example in ARC doc.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162933 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/AutomaticReferenceCounting.html b/docs/AutomaticReferenceCounting.html
index 5cacbd5..5354f8a 100644
--- a/docs/AutomaticReferenceCounting.html
+++ b/docs/AutomaticReferenceCounting.html
@@ -1904,9 +1904,9 @@
 
 <p>A pragma is provided to facilitate the mass annotation of interfaces:</p>
 
-<pre>#pragma arc_cf_code_audited begin
+<pre>#pragma clang arc_cf_code_audited begin
 ...
-#pragma arc_cf_code_audited end</pre>
+#pragma clang arc_cf_code_audited end</pre>
 
 <p>All C functions declared within the extent of this pragma are
 treated as if annotated with the <tt>cf_audited_transfer</tt>