net/mlx5: Remove XFRM no_trailer flag

Only FPGA needed this NO_TRAILER flag, so remove this assignment.

Link: https://lore.kernel.org/r/636d75421e1ca4254a062537eea001ab0e50e19b.1649232994.git.leonro@nvidia.com


Reviewed-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>