staging: comedi: drivers: use comedi_dio_update_state() for simple cases

commit 97f4289ad08cffe55de06d4ac4f89ac540450aee upstream.

[Split from original patch subject: "staging: comedi: drivers: use
comedi_dio_update_state() for simple cases"]

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state for simple cases where the hardware is updated
when any channel is modified.

Also, fix a bug in the amplc_pc263 and amplc_pci263 drivers where the
current state is not returned in data[1].

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>