s390/vfio-ap: handle hardware checkstop state on queue reset operation

s390/vfio-ap: handle hardware checkstop state on queue reset operation

Update vfio_ap_mdev_reset_queue() to handle an unexpected checkstop (hardware error) the
same as the deconfigured case. This prevents unexpected and unhelpful warnings in the
event of a hardware error.

We also stop lying about a queue's reset response code. This was originally done so we
could force vfio_ap_mdev_filter_matrix to pass a deconfigured device through to the guest
for the hotplug scenario. vfio_ap_mdev_filter_matrix is instead modified to allow
passthrough for all queues with reset state normal, deconfigured, or checkstopped. In the
checkstopped case we choose to pass the device through and let the error state be
reflected at the guest level.

Signed-off-by: "Jason J. Herne" <jjherne@linux.ibm.com>
Reviewed-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Link: https://lore.kernel.org/r/20240215153144.14747-1-jjherne@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>