net/mlx5e: Generalize open RQ

Unify RQ creation for different RQ types. For each RQ type add a
separate open helper which initializes the RQ specific values and
trigger a call for generic open RQ function. Avoid passing the
mlx5e_channel pointer to the generic open RQ as a container, since the
RQ may reside under a different type of channel.

Signed-off-by: Aya Levin <ayal@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>