ice: Enable VSI Rx/Tx pruning only when VLAN 0 is active

VLAN pruning is not valid when VLAN 0 is not active. If VLAN
pruning is enabled and VLAN 0 is not active (8021q driver not loaded)
then normal, non-VLAN, traffic will not pass.

TX/RX VLAN pruning is enabled when the VLAN 0 is added to the
active_vlan bitmap and it is disabled when VLAN 0 is removed from the
active_vlan bitmap.

So, only enable VLAN pruning when VLAN 0 is active. Setting RX VLAN
pruning causes the switch to drop received VLAN packets when there
are no matching VLAN ids in the associated VSI's switch filters. Setting
TX pruning makes it so the switch will not send out any packets with
VLAN tags that don't match the associated VSI's switch filters.

With this patch, if the VF or PF tries to send a VLAN tagged packet with
a VLAN tag that it does not have a pruning rule for it will trigger an
MDD event. For example, if PF0 has VLAN10 and VLAN11 interfaces and
scapy is used to send a packet with VLAN8 then the MDD is triggered.

Also make ice_vsi_kill_vlan return a value which the caller can check
before updating VLAN related data structures (counts, pruning bits, etc.).

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>