[media] tuner-core: Don't touch at standby during tuner_lookup

It makes no sense that tuner_lookup would touch at the standby
state. Remove it.

Thanks-to: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/tuner-core.c

···
 			continue;
 
 		mode_mask = pos->mode_mask;
-		pos->standby = 1;
 		if (*radio == NULL && mode_mask == T_RADIO)
 			*radio = pos;
 		/* Note: currently TDA9887 is the only demod-only