net/mlx5e: Fix outer_header_zero() check size

outer_header_zero() routine checks if the outer_headers match of a
flow-table entry are all zero.

This function uses the size of whole fte_match_param, instead of just
the outer_headers member, causing failure to detect all-zeros if
any other members of the fte_match_param are non-zero.

Use the correct size for zero check.

Fixes: 6dc6071cfcde ("net/mlx5e: Add ethtool flow steering support")
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en_fs_ethtool.c

@@ -276,7 +276,7 @@ static void add_rule_to_list(struct mlx5e_priv *priv,
 
 static bool outer_header_zero(u32 *match_criteria)
 {
-	int size = MLX5_ST_SZ_BYTES(fte_match_param);
+	int size = MLX5_FLD_SZ_BYTES(fte_match_param, outer_headers);
 	char *outer_headers_c = MLX5_ADDR_OF(fte_match_param, match_criteria,
 					     outer_headers);