staging: comedi: ni_660x: remove BUG_ON(chan >= NUM_PFI_CHANNELS)

This BUG_ON can never happen. The 'chan' value comes from the comedi
core in the insn->chanspec and will always be in range for the subdevice
number of channels (s->n_chan = NUM_PFI_CHANNELS).
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/ni_660x.c

@@ -1106,7 +1106,6 @@ static int ni_660x_set_pfi_routing(struct comedi_device *dev, unsigned chan,
 		if (source == pfi_output_select_do)
 			return -EINVAL;
 	}
-	BUG_ON(chan >= NUM_PFI_CHANNELS);
 
 	devpriv->pfi_output_selects[chan] = source;
 	if (devpriv->pfi_direction_bits & (((uint64_t) 1) << chan))
@@ -1120,7 +1119,6 @@ static unsigned ni_660x_get_pfi_routing(struct comedi_device *dev,
 {
 	struct ni_660x_private *devpriv = dev->private;
 
-	BUG_ON(chan >= NUM_PFI_CHANNELS);
 	return devpriv->pfi_output_selects[chan];
 }