net/mlx5e: Fix build break on 32bit

The cited commit caused the following build break in mlx5 due to a change
in size of MAX_SKB_FRAGS.

error: format '%lu' expects argument of type 'long unsigned int',
       but argument 7 has type 'unsigned int' [-Werror=format=]

Fix this by explicit casting.

Fixes: 3948b05 ("net: introduce a config option to tweak MAX_SKB_FRAGS")
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Link: https://lore.kernel.org/r/20230328200723.125122-1-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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

@@ -5725,8 +5725,8 @@ int mlx5e_attach_netdev(struct mlx5e_priv *priv)
 
 	/* Validate the max_wqe_size_sq capability. */
 	if (WARN_ON_ONCE(mlx5e_get_max_sq_wqebbs(priv->mdev) < MLX5E_MAX_TX_WQEBBS)) {
-		mlx5_core_warn(priv->mdev, "MLX5E: Max SQ WQEBBs firmware capability: %u, needed %lu\n",
-			       mlx5e_get_max_sq_wqebbs(priv->mdev), MLX5E_MAX_TX_WQEBBS);
+		mlx5_core_warn(priv->mdev, "MLX5E: Max SQ WQEBBs firmware capability: %u, needed %u\n",
+			       mlx5e_get_max_sq_wqebbs(priv->mdev), (unsigned int)MLX5E_MAX_TX_WQEBBS);
 		return -EIO;
 	}