net/mlx5: Bridge, fix multicast packets sent to uplink

To enable multicast packets which are offloaded in bridge multicast
offload mode to be sent also to uplink, FTE bit uplink_hairpin_en should
be set. Add this bit to FTE for the bridge multicast offload rules.

Fixes: 18c2916c ("net/mlx5: Bridge, snoop igmp/mld packets")
Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>