staging: comedi: comedi_fops: checkpatch.pl --strict cleanup

Fix the checkpatch.pl --strict issues:

CHECK: braces {} should be used on all arms of this statement
CHECK: Alignment should match open parenthesis
CHECK: Prefer kzalloc(sizeof(*dev)...) over kzalloc(sizeof(struct comedi_device)...)

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>