E810 LACP packets handling

Hi there!

I'm faced with unexpected behavior when try to send LACP packet to port under testpmd control. Here is what I did :

1. Bind port to igb_uio driver:
```
sudo usertools/dpdk-devbind.py --unbind 0000:8b:00.7
sudo usertools/dpdk-devbind.py --bind=igb_uio 0000:8b:00.7
```
2. Run testpmd:
```
sudo ./dpdk-testpmd --log-level=debug -l 2,3 -- -i
```
3. Start forwarding:
```
testpmd> start tx_firs
```
4. Send from another server LACP packet to port under testpmd control
5. Show xstats and it's all good for now:
```
testpmd> show port xstats 0
rx_good_packets: 4
rx_unknown_protocol_packets: 0
```
6. reset port 0
```
testpmd> stop
testpmd> port stop 0
testpmd> port reset 0
testpmd> port start all
testpmd> start tx_firs
```
7. Send from another server LACP packet to port under testpmd control
8. Show xstats and see that `rx_unknown_protocol_packets` encountered:
```
rx_good_packets: 0
rx_unknown_protocol_packets: 4
```
Configuration: E810 NIC, firmware-version: 3.10, DPDK version: 21.11.0.

I don't know if this behavior is normal, but I would like the LACP traffic not to be dropped by the card. Thanks!

I already created an issue with the same problem in the Intel community, but I didn't get any advice. So I decided to try my luck here.

Here is the link to the issue in the Intel community:
https://community.intel.com/t5/Ethernet-Products/E810-LACP-handing/m-p/1662359#M39933