net/mlx5e: Refactor RSS related objects and code

In order to use RSS for hairpin, we refactor the code that deals with
setup of the TTC steering tables. This is done using an interim ttc
params object that has the flow table attributes, TIR numbers, etc.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>