staging: dgnc: Siplify the dgnc_start function

This commit slightly simplifies the sgnc_start() function by
rearranging it. As a result the indentation level is reduced.
This is not the functional change.

Signed-off-by: Konrad Zapalowicz <bergo.torino@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>