[PATCH] bonding: Allow ARP target table to have empty entries

With the sysfs interface, the user can remove entries from the ARP table
at runtime.  The ARP monitor code now allows for empty entries in the
table.

Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Acked-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>