net/mlx5: Allow future addition of IPsec object modifiers

Currently, all released FW versions support only two IPsec object
modifiers, and modify_field_select get and set same value with
proper bits.

However, it is not future compatible, as new FW can have more
modifiers and "default" will cause to overwrite not-changed fields.

Fix it by setting explicitly fields that need to be overwritten.

Fixes: 7ed92f97 ("net/mlx5e: IPsec: Add Connect-X IPsec ESN update offload support")
Signed-off-by: Huy Nguyen <huyn@nvidia.com>
Reviewed-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_offload.c

@@ -179,6 +179,9 @@ static int mlx5_modify_ipsec_obj(struct mlx5e_ipsec_sa_entry *sa_entry,
 		return -EOPNOTSUPP;
 
 	obj = MLX5_ADDR_OF(modify_ipsec_obj_in, in, ipsec_object);
+	MLX5_SET64(ipsec_obj, obj, modify_field_select,
+		   MLX5_MODIFY_IPSEC_BITMASK_ESN_OVERLAP |
+			   MLX5_MODIFY_IPSEC_BITMASK_ESN_MSB);
 	MLX5_SET(ipsec_obj, obj, esn_msb, attrs->esn);
 	if (attrs->flags & MLX5_ACCEL_ESP_FLAGS_ESN_STATE_OVERLAP)
 		MLX5_SET(ipsec_obj, obj, esn_overlap, 1);