No ETIME on OpenBSD (STREAMS errno extension).

Index: shared/file-util.c
--- shared/file-util.c.orig
+++ shared/file-util.c
@@ -45,13 +45,13 @@ current_time_str(char *str, size_t len, const char *fm
 	t = time(NULL);
 	t_local = localtime(&t);
 	if (!t_local) {
-		errno = ETIME;
+		errno = EINVAL;
 		return -1;
 	}
 
 	ret = strftime(str, len, fmt, t_local);
 	if (ret == 0) {
-		errno = ETIME;
+		errno = EINVAL;
 		return -1;
 	}
 
