staging: dgnc: Fix unnecessary braces warning.

Fixes "braces {} are not necessary for single statement blocks"
checkpatch.pl warnings in dgnc_sysfs.c

Signed-off-by: Gulsah Kose <gulsah.1004@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>