net/mlx5e: Fix MPLSoUDP encap to use MPLS action information

Currently the MPLSoUDP encap builds the MPLS header using encap action
information (tunnel id, ttl and tos) instead of the MPLS action
information (label, ttl, tc and bos) which is wrong.

Fix by storing the MPLS action information during the flow action
parse and later using it to create the encap MPLS header.

Fixes: f828ca6a

 ("net/mlx5e: Add support for hw encapsulation of MPLS over UDP")
Signed-off-by: Maor Dickman <maord@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>