be2net: covert vlan array to bit-map

This patch converts the vlan u8[] used to track vlan-id
membership to a bit-map as it reduces memory usage.

Signed-off-by: Ravikumar Nelavelli <ravikumar.nelavelli@emulex.com>
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>