fix syntax error
pve-common: PVE/Network: rework of activate_bridge_vlan

- use ip command instead of old vconfig
- activate gvrp by default (it doesn't harm if the switch does not support it or it is disabled)
- use bridge instead of raw ethernet device as vlan bridge

Signed-off-by: Stefan Priebe <s.priebe@profihost.ag>
bmump version to 1.0-44