src: use osmo_timer_setup()

Use new function available in libosmocore to set up timers. Compile
tested only.

Change-Id: I4ca4950e49a09c63b608b13ac7561ebbd351889a
diff --git a/src/input/unixsocket.c b/src/input/unixsocket.c
index 4f287ae..63bd796 100644
--- a/src/input/unixsocket.c
+++ b/src/input/unixsocket.c
@@ -160,8 +160,7 @@
 	}
 
 	/* set tx delay timer for next event */
-	e1i_ts->sign.tx_timer.cb = timeout_ts1_write;
-	e1i_ts->sign.tx_timer.data = e1i_ts;
+	osmo_timer_setup(&e1i_ts->sign.tx_timer, timeout_ts1_write, e1i_ts);
 
 	osmo_timer_schedule(&e1i_ts->sign.tx_timer, 0, e1i_ts->sign.delay);