qlcnic: Fix tunnel offload for 82xx adapters

Qlogic's 82xx series adapter doesn't support
tunnel offloads, driver incorrectly assumes that it is
supported and causes firmware hang while running tunnel IO.

This patch fixes this by not advertising tunnel offloads
for 82xx adapters.

Signed-off-by: Manish Chopra <manish.chopra@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>