spice.proto: add SPICE_MSG_MAIN_MIGRATE_END & SPICE_MSGC_MAIN_MIGRATE_END
spice.proto: add SPICE_MSG_MAIN_MIGRATE_END & SPICE_MSGC_MAIN_MIGRATE_END

(cherry picked from commit cfbd07710562e522179ae5a7085a789489a821bb branch 0.8)

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