media: vidtv: simplify PCR logic to get jiffies

There's no need to have a check when setting timing.past_jiffies,
as we can simply do the initialization earlier at vidtv_mux_init().
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/test-drivers/vidtv/vidtv_mux.c

@@ -100,11 +100,7 @@ static void vidtv_mux_update_clk(struct vidtv_mux *m)
 	/* call this at every thread iteration */
 	u64 elapsed_time;
 
-	/* this will not hold a value yet if we have just started */
-	m->timing.past_jiffies = m->timing.current_jiffies ?
-				 m->timing.current_jiffies :
-				 get_jiffies_64();
-
+	m->timing.past_jiffies = m->timing.current_jiffies;
 	m->timing.current_jiffies = get_jiffies_64();
 
 	elapsed_time = jiffies_to_usecs(m->timing.current_jiffies -
@@ -449,6 +445,7 @@ struct vidtv_mux *vidtv_mux_init(struct dvb_frontend *fe,
 	m->pcr_pid = args.pcr_pid;
 	m->transport_stream_id = args.transport_stream_id;
 	m->priv = args.priv;
+	m->timing.current_jiffies = get_jiffies_64();
 
 	if (args.channels)
 		m->channels = args.channels;