net/mlx5e: Fix ETS BW check

[ Upstream commit ff0891915cd7b24ab27eee9b360c0452853bf9f6 ]

Fix bug that allows ets bw sum to be 0% when ets tc type exists.

Fixes: 08fb1dac ('net/mlx5e: Support DCBNL IEEE ETS')
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Reviewed-by: Huy Nguyen <huyn@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>