ipwrapper: fix version to family parameter name

In commit e435e680fdae8f1baaf8dac549c72db32c07549f there is a change
to add ipv6 support to various ipwrapper functions. During the
review process it was suggested to change the parameter from
'version' to 'family' but I missed one of the parameters.

Change-Id: I2ee57be88cb0037a337bfa28aa296cd01c8799a7
Signed-off-by: Antoni S. Puimedon <asegurap@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/28095
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Tested-by: Dan Kenigsberg <danken@redhat.com>