Add a missing =back to eliminate error.

llvm-svn: 27878
diff --git a/llvm/docs/CommandGuide/llvmc.pod b/llvm/docs/CommandGuide/llvmc.pod
index 0767212..491e1ff 100644
--- a/llvm/docs/CommandGuide/llvmc.pod
+++ b/llvm/docs/CommandGuide/llvmc.pod
@@ -337,6 +337,8 @@
 their own configuration directories in addition to the standard ones to which 
 they may not have write access.
 
+=back
+
 
 =head2 Unimplemented Options