Rather than relying on a notifier for associating the KVM with
the group, let's assume that the association has already been
made prior to device_open.  The first time a device is opened
associate the group KVM with the device.

This fixes a user-triggerable oops in GVT.
Reviewed-by: NTony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: NJason Gunthorpe <jgg@nvidia.com>
Acked-by: NZhi Wang <zhi.a.wang@intel.com>
Link: https://lore.kernel.org/r/20220519183311.582380-2-mjrosato@linux.ibm.comSigned-off-by: NAlex Williamson <alex.williamson@redhat.com>