twrpTar: Fix uninitialized current_archive_type

* current_archive_type is not properly initialized
  leading to a potential random close(fd) in closeTar()

Change-Id: I1598ba4d524b723b8175ee847e2b1c5aeedbd938

twrpTar.cpp

@@ -1102,6 +1102,7 @@ int twrpTar::createTar() {
 		}
 	} else {
 		// Not compressed or encrypted
+		current_archive_type = UNCOMPRESSED;
 		init_libtar_buffer(0, progress_pipe_fd);
 		if (part_settings->adbbackup) {
 			LOGINFO("Opening TW_ADB_BACKUP uncompressed stream\n");