net/mlx5e: Be consistent with bitmap handling of link modes

Use the bitmap operations when accessing the advertised/supported link
modes and remove places that access them as arrays of unsigned longs
(underlying implementation of the bitmap), this makes the code much more
readable and clear.

Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20240808055927.2059700-6-tariqt@nvidia.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>