Merge pull request #15958 from vdemeester/14570-contrib-completion-image

Add docker ps --filter=… ancestor image bash completion

contrib/completion/bash/docker

@@ -975,6 +975,11 @@ _docker_ps() {
 	esac
 
 	case "${words[$cword-2]}$prev=" in
+		*ancestor=*)
+			cur="${cur#=}"
+			__docker_images
+			return
+			;;
 		*id=*)
 			cur="${cur#=}"
 			__docker_container_ids