staging: comedi: usbdux: add missing spaces

Add some missing space to quiet the checkpatch.pl issues about:

CHECK: spaces preferred around that '/' (ctx:VxV)
CHECK: spaces preferred around that '*' (ctx:VxV)
CHECK: spaces preferred around that '+' (ctx:VxV)

For aesthetics, use tabs instead of spaces in all the defines and

ensure they have common alignment.

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>