mlxsw: core_env: Query and store port module's type during initialization

Query and store port module's type during initialization so that it
could be later used to determine if certain configurations are allowed
based on the type.

Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>