comedi: rtd520: if condition with no effect - if identical to else

The if and the else branch code are identical - so the condition has no
effect on the effective code - this patch removes the condition and the
duplicated code.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>