ubus: fix uc_ubus_have_uloop for eloop+uloop combination

When uloop has been integrated with eloop (in hostapd/wpa_supplicant),
uloop_cancelling will return false, since uloop_run is not being called.
This leads to ubus.defer() calling uloop_run in a context where it can
prevent the other event loop from running.

Fix this by detecting event loop integration via uloop_fd_set_cb being set

Signed-off-by: Felix Fietkau <[email protected]>

lib/ubus.c

@@ -665,6 +665,9 @@ uc_ubus_have_uloop(void)
 	bool prev = uloop_cancelled;
 	bool active;
 
+	if (uloop_fd_set_cb)
+		return true;
+
 	uloop_cancelled = true;
 	active = uloop_cancelling();
 	uloop_cancelled = prev;