net/mlx5e: RX handlers per netdev profile

In order to have different RX handler per profile, fix and refactor the
current code to take the rx handler directly from the netdevice profile
rather than computing it on runtime as it was done with the switchdev
mode representor rx handler.

This will also remove the current wrong assumption in mlx5e_alloc_rq
code that mlx5e_priv->ppriv is of the type vport_rep.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Erez Shitrit <erezsh@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>