be2net: Fix to avoid hardware workaround when not needed

Hardware workaround requesting hardware to skip vlan insertion is necessary
only when umc or qnq is enabled. Enabling this workaround in other scenarios
could cause controller to stall.

Signed-off-by: Sarveshwar Bandi <sarveshwar.bandi@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>