TODO: exdev handling still broken on nvmutil

Signed-off-by: Leah Rowe <leah@libreboot.org>

util/libreboot-utils/lib/io.c

@@ -456,6 +456,8 @@ gbe_mv(void)
 	if (errno != EXDEV)
 		goto ret_gbe_mv;
 
+	err(errno, "TODO: cross-filesystem atomic writes currently broken");
+
 	/*
 	 * cross-filesystem: copy into target dir tmp
 	 */