V4L/DVB: cx88: fix setting input when using DVB

In cx88-mpeg.c, there is code that sets core->input to CX88_VMUX_DVB.
However, this may be incorrect, since core->input is actually an
index to core->board.input[], which has not enough elements to be
indexed by the value of CX88_VMUX_DVB. So, the modified code searches
core->board.input[] for an input with a type of CX88_VMUX_DVB, and if
it does not find one, the index is simply set to zero.
The change may not have much effect, though, since it appears the only
case when core->input is actually used is when the current input is
being queried.

Signed-off-by: Istvan Varga <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/cx88/cx88-mpeg.c

···
 static int cx8802_request_acquire(struct cx8802_driver *drv)
 {
 	struct cx88_core *core = drv->core;
+	unsigned int	i;
 
 	/* Fail a request for hardware if the device is busy. */
 	if (core->active_type_id != CX88_BOARD_NONE &&
 	    core->active_type_id != drv->type_id)
 		return -EBUSY;
 
-	core->input = CX88_VMUX_DVB;
+	core->input = 0;
+	for (i = 0;
+	     i < (sizeof(core->board.input) / sizeof(struct cx88_input));
+	     i++) {
+		if (core->board.input[i].type == CX88_VMUX_DVB) {
+			core->input = i;
+			break;
+		}
+	}
 
 	if (drv->advise_acquire)
 	{