staging: comedi: amplc_pci230: don't begin line with binary operator

If an expression involving a binary operator needs to be split across
two lines, put the split after the operator.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>