bonding: Remove unnecessary returned value check

The function bond_info_query alwarys returns 0. As such, in the function
bond_do_ioctl, it is not necessary to check the returned value. So the
interface type of the function bond_info_query is changed to void. The
redundant check is removed.

Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>