Fix monitor state change for newer kernels/iproute

On el6 kernels adding a vlan over a link doesn't create an entry for
the link under the vlan. On f19+ kernels it does happen, so we need
to check that the state change instead of just checking if there is
some state reported.

Change-Id: I759b0b8fdd7794a50fe1a0e630691592a4c45946
Signed-off-by: Antoni S. Puimedon <asegurap@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/20496
Reviewed-by: Dan Kenigsberg <danken@redhat.com>