bnx2x: fix detection of VLAN filtering feature for VF

VFs are currently missing the VLAN filtering feature, because we were
checking the PF's acquire response before actually performing the acquire.

Fix it by setting the feature flag later when we have the PF response.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>