staging: comedi: daqboard2000: use comedi_timeout()

Use comedi_timeout() to wait for the analog input pipe full, scanning,
amd end-of-conversion status. The status to check it passed as the
'context' to comedi_timeout().

Use comedi_timeout() to wait for the analog output end-of-conversion.

This also fixes a possible bug where invalid data is returned for the
analog input read if the conversion did not complete, The analog
output has a similar possible bug where the cached readback value is
incorrect if the conversion times out.

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>