ice: refactor devlink_port to be per-VSI

Currently, the devlink_port structure is stored within the ice_pf. This
made sense because we create a single devlink_port for each PF. This
setup does not mesh with the abstractions in the driver very well, and
led to a flow where we accidentally call devlink_port_unregister twice
during error cleanup.

In particular, if devlink_port_register or devlink_port_unregister are
called twice, this leads to a kernel panic. This appears to occur during
some possible flows while cleaning up from a failure during driver
probe.

If register_netdev fails, then we will call devlink_port_unregister in
ice_cfg_netdev as it cleans up. Later, we again call
devlink_port_unregister since we assume that we must cleanup the port
that is associated with the PF structure.

This occurs because we cleanup the devlink_port for the main PF even
though it was not allocated. We allocated the port within a per-VSI
function for managing the main netdev, but did not release the port when
cleaning up that VSI, the allocation and destruction are not aligned.

Instead of attempting to manage the devlink_port as part of the PF
structure, manage it as part of the PF VSI. Doing this has advantages,
as we can match the de-allocation of the devlink_port with the
unregister_netdev associated with the main PF VSI.

Moving the port to the VSI is preferable as it paves the way for
handling devlink ports allocated for other purposes such as SR-IOV VFs.

Since we're changing up how we allocate the devlink_port, also change
the indexing. Originally, we indexed the port using the PF id number.
This came from an old goal of sharing a devlink for each physical
function. Managing devlink instances across multiple function drivers is
not workable. Instead, lets set the port number to the logical port
number returned by firmware and set the index using the VSI index
(sometimes referred to as VSI handle).

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>