qed: !main_ptt for tunnel configuration

Flows configuring tunnel ports in HW use the main_ptt which should
be reserved for core-functionality.

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