net/tap: fix some flow collision

net/tap: fix some flow collision

The following two flow rules (testpmd syntax) should not collide:
flow create 0 priority 1 ingress pattern eth / ipv4 / end actions drop / end
flow create 0 priority 1 ingress pattern eth / ipv6 / end actions drop / end

But the eth_type in the associated TC rule was set to either "ip" or
"ipv6".  For TC, they could thus not have the same priority.

Use ETH_P_ALL only in the TC message to make sure those rules can
coexist.

Fixes: de96fe68ae95 ("net/tap: add basic flow API patterns and actions")
Cc: stable@dpdk.org
Signed-off-by: Pascal Mazon <pascal.mazon@6wind.com>