Get rid of the ugly CMD_CHFLAG macro and use a const string (eg "dDU") in the

command entry structs and a couple of functions to check/set the flags.

cmd-unbind-key.c

@@ -40,7 +40,7 @@ struct cmd_unbind_key_data {
 const struct cmd_entry cmd_unbind_key_entry = {
 	"unbind-key", "unbind",
 	"[-cn] [-t key-table] key",
-	0, 0,
+	0, "",
 	NULL,
 	cmd_unbind_key_parse,
 	cmd_unbind_key_exec,