staging: comedi: pcl711: Fix endian problem for AI command data

staging: comedi: pcl711: Fix endian problem for AI command data

BugLink: https://bugs.launchpad.net/bugs/1919492
commit a084303a645896e834883f2c5170d044410dfdb3 upstream.

The analog input subdevice supports Comedi asynchronous commands that
use Comedi's 16-bit sample format.  However, the call to
`comedi_buf_write_samples()` is passing the address of a 32-bit integer
variable.  On bigendian machines, this will copy 2 bytes from the wrong
end of the 32-bit value.  Fix it by changing the type of the variable
holding the sample value to `unsigned short`.

Fixes: 1f44c034de2e ("staging: comedi: pcl711: use comedi_buf_write_samples()")
Cc: <stable@vger.kernel.org> # 3.19+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20210223143055.257402-9-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>