High: IPaddr2: make sure that some ARP send program runs

This is a regression fix which got introduced in commit
a5305b91dd1d2199a75f44130d1d963a7e789e8c:

commit a5305b91dd1d2199a75f44130d1d963a7e789e8c
Author: Dejan Muhamedagic <dejan@suse.de>
Date: Sat Nov 10 20:21:45 2012 +0100

Medium: IPaddr2: use send_arp instead of ipoibarping if not

available