VLAN Priority Control for Control Plane Traffic on A10-Interface

[Istvan91]

Is your feature request related to a problem? Please describe.

I cannot configure the vlan-priority for control plane traffic on a10-interfaces. So

1. control plane packets get dropped in QoS tests (that's problem with ppp/lcp)
2. cannot verify if control plane packets are handled properly by the DUTs QoS configuration.

Describe the solution you'd like

A configuration to set the vlan priority for control plan traffic on a10-interfaces.

Describe alternatives you've considered

I can't think of any alternative without putting some hardware inbetween to do the marking for me.

Additional context

A similar feature exists already for the client side. There it is possible to configure priority marking for pppoe/dhcp/dhcpv6. Since the A10 is used in a Layer2 context, I think it would be enough to have a single configuration for vlan-priority for all control plane packets. Dedicated configuration for each protocol type is imho not necessary, though nice to have.