staging: comedi: addi_apci_1516: cleanup the s->subdev_flags
The flags SDF_GROUND and SDF_COMMON only have meaning for analog
input/output subdevices. Remove these flags from the digital
input/output and timer subdevices in this driver.
The digital output subdevice does not need the SDF_READABLE flags.
Remove it.
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>