[media] au8522: Set the initial modulation

We need to set the initial modulation on driver setup, or else any
calls to GET_FRONTEND prior to the first SET_FRONTEND call will get
back garbage.

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

drivers/media/dvb-frontends/au8522_common.c

···
 	   chip, so that when it gets powered back up it won't think
 	   that it is already tuned */
 	state->current_frequency = 0;
+	state->current_modulation = VSB_8;
 
 	au8522_writereg(state, 0xa4, 1 << 5);