net/mlx5e: Validate BW weight values of ETS

Valid weight assigned to ETS TClass values are 1-100

Fixes: 08fb1dac

 ('net/mlx5e: Support DCBNL IEEE ETS')
Signed-off-by: Rana Shahout <ranas@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>