Fix pg_restore -l with the directory archive to display the correct format name.

Back-patch to 9.1 where the directory archive was introduced.

src/bin/pg_dump/pg_backup_archiver.c

@@ -885,6 +885,9 @@ PrintTOCSummary(Archive *AHX, RestoreOptions *ropt)
 		case archCustom:
 			fmtName = "CUSTOM";
 			break;
+		case archDirectory:
+			fmtName = "DIRECTORY";
+			break;
 		case archTar:
 			fmtName = "TAR";
 			break;