hw/qxl: fix cpr

hw/qxl: fix cpr

During normal migration, new QEMU creates and initializes memory regions,
then loads the preserved contents of the region from vmstate.

During CPR, memory regions are preserved in place, then the realize
method initializes the regions contents, losing the old contents.  To
fix, skip writes to the qxl memory regions during CPR load.

Reported-by: andrey.drobyshev@virtuozzo.com
Tested-by: andrey.drobyshev@virtuozzo.com
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Message-ID: <1741380954-341079-5-git-send-email-steven.sistare@oracle.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>