config: ensure that both ABI and MODULE are specified before the properties

If we have properties, strtok will return strings from there as tokens
and the error will appear later as we will attempt to parse an incomplete
GVariant. It is better to catch this early so that we can print a more
useful error message.

src/main.c

@@ -152,7 +152,9 @@ parse_commands_file (struct WpDaemonData *d, GInputStream * stream,
           abi = strtok_r (NULL, " ", &saveptr);
           module = strtok_r (NULL, " ", &saveptr);
 
-          if (!abi || !module) {
+          if (!abi || !module ||
+              (abi && abi[0] == '{') || (module && module[0] == '{'))
+          {
             g_set_error (error, WP_DOMAIN_DAEMON, WP_CODE_INVALID_ARGUMENT,
                 "expected ABI and MODULE at line %i", lineno);
             return FALSE;