Prevent seg fault in off nominal path when registered option fails to validate

If an option is registered to a type and it is the last known type in the list
of registered types, and the option fails to register, an overrun of the types
array can occur due to the index variable having been already incremented.



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@397568 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/config_options.c

@@ -188,7 +188,7 @@ static int link_option_to_types(struct aco_info *info, struct aco_type **types,
 #endif /* AST_XML_DOCS */
 		) {
 			do {
-				ao2_unlink(types[idx]->internal->opts, opt);
+				ao2_unlink(types[idx - 1]->internal->opts, opt);
 			} while (--idx);
 			return -1;
 		}