net:dl2k: Modify the code style escaping the warning

modify the code style in order to removing the following warning
when excute the script checkpatch.pl
WARNING: space prohibited between function name and open parenthesis '('

Signed-off-by: Huang Zijiang <huang.zijiang@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>