config: add default font when using the default config

When there is no configuration file, and we're using the default
configuration, we accidentally jumped pasted the code that ensures
we have at least "monospace" in the font list.

config.c

@@ -562,10 +562,10 @@ config_load(struct config *conf, const char *conf_path)
     ret = parse_config_file(f, conf, conf_path);
     fclose(f);
 
+out:
     if (ret && tll_length(conf->fonts) == 0)
         tll_push_back(conf->fonts, strdup("monospace"));
 
-out:
     free(default_path);
     return ret;
 }