wpa_s->dbus_groupobj_path is always NULL so suppress to show it.
This was found by gcc 9.2.1 warning.
dbus/dbus_new.c: In function ‘wpas_dbus_unregister_p2p_group’:
dbus/dbus_new.c:4793:3: warning: ‘%s’ directive argument is null [-Wformat-overflow=]
4793 | wpa_printf(MSG_DEBUG,
| ^~~~~~~~~~~~~~~~~~~~~
4794 | "%s: Group object '%s' already unregistered",
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4795 | __func__, wpa_s->dbus_groupobj_path);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Masashi Honma <masashi.honma@gmail.com>
b38c8c9cb2