net/mlx5e: replace EINVAL in mlx5e_flower_parse_meta()

The drivers reports EINVAL to userspace through netlink on invalid meta
match. This is confusing since EINVAL is usually reserved for malformed
netlink messages. Replace it by more meaningful codes.

Fixes: 6d65bc64 ("net/mlx5e: Add mlx5e_flower_parse_meta support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>