mlxsw: spectrum_acl: Add vregion migration end tracepoint

Hit the new tracepoint once the vregion migration ends.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>