cppcheck: fix warns

src/cntlr_commands_impl.c

@@ -80,7 +80,7 @@ int COMMAND(help)(void *priv, void *args, void *out)
 
 		aa = blobmsg_open_array(bb, "commands");
 		controller_for_each_command(cmd) {
-			void *a, *t, *tt;
+			void *tt;
 
 			tt = blobmsg_open_table(bb, "");
 			blobmsg_add_string(bb, "command", cmd->command);