smartcard: fix calc of remaining data size when reading more than one msg from the device
smartcard: fix calc of remaining data size when reading more than one msg from the device

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