ice: do switchdev slow-path Rx using PF VSI

Add an ICE_RX_FLAG_MULTIDEV flag to Rx ring.

If it is set try to find correct port representor. Do it based on
src_vsi value stored in flex descriptor. Ids of representor pointers
stored in xarray are equal to corresponding src_vsi value. Thanks to
that we can directly get correct representor if we have src_vsi value.

Set multidev flag during ring configuration.

If the mode is switchdev, change the ring descriptor to the one that
contains src_vsi value.

PF netdev should be reconfigured, do it by calling ice_down() and
ice_up() if the netdev was up before configuring switchdev.

Reviewed-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>