ice: Remove node before releasing VSI

Before releasing the VSI, remove the VSI scheduler node. If not,
the node is left in the scheduler tree and, on subsequent load, the
scheduler tree contains the node so it does not set it in vsi_ctx.
This, later, causes the node to not be found in ice_sched_get_free_qparent
which leads to a "Failed to set LAN Tx queue context, error: -1".

To remove the scheduler node, this patch introduces ice_rm_vsi_lan_cfg
and related helpers.

Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>