net/mlx5: remove checks for outer tunnel items on E-Switch

net/mlx5: remove checks for outer tunnel items on E-Switch

This patch removes unnecessary outer tunnel parameters check in the
validation routine for the E-Switch Flows. IPv4/IPv6 may have any
spec and mask, and transferred to tc without changes, all checks
are performed by kernel.

We are going to support Flows matching with outer tunnel items
and not containing the explicit tunnel decap action (this one
might be drop, redirect or table jump, for exapmle). So we can
not rely on presence of tunnel decap action in the list to decide
whether the Flow is for tunnel, instead we will use the presence
of tunnel item (like RTE_FLOW_ITEM_TYPE_VXLAN) in the item list.
The tunnel pattern checks within Flow validation routine are
rebound to presence of tunnel item. VXLAN decap action checks
for presence of VXLAN VNI item.

The tunnel UDP item is checked at the point of processing the tunnel
item (i.e. VXLAN). We can not perform UDP item check as tunnel once
UDP item encountered in the list, because it is not known yet whether
the tunnel item follows. The pointer to UDP item is saved and
checked as outer ones if tunnel item found.

Cc: stable@dpdk.org
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Shahaf Shuler <shahafs@mellanox.com>