spice: fix server crush in case connecting without qxl device
spice: fix server crush in case connecting without qxl device

Signed-off-by: Izik Eidus <0f4d5ad8fceb71158793af13424905ac12569440@redhat.com>

elmarco/spice,freedesktop-unofficial-mirror/spice__spice,Fantu/spice,dezelin/spice,ya-mouse/spice,alon/spice-server,SPICE/spice,fgouget/spice,freedesktop-unofficial-mirror/spice__spice,alon/spice-server,freedesktop-unofficial-mirror/spice__spice,mathslinux/spice,Fantu/spice,ya-mouse/spice,dezelin/spice,elmarco/spice,fgouget/spice,fgouget/spice,freedesktop-unofficial-mirror/spice__spice,virtualAMP/spiceplay,virtualAMP/spiceplay,SPICE/spice,elmarco/spice,alon/spice-server,virtualAMP/spiceplay,freedesktop-unofficial-mirror/spice__spice,Fantu/spice,Fantu/spice,ya-mouse/spice,fgouget/spice,mathslinux/spice,dezelin/spice,alon/spice-server,mathslinux/spice,elmarco/spice,dezelin/spice,virtualAMP/spiceplay,mathslinux/spice,SPICE/spice,alon/spice-server,mathslinux/spice,dezelin/spice,elmarco/spice