lua log(): make it work again

sandbox.lua:72: attempt to call global 'log_notice' (a nil value)

Broken by commit 39dd89db (MR !1208 (merged))

daemon/lua/sandbox.lua.in

@@ -60,6 +60,10 @@ function log_warn(grp, fmt, ...)
 	log_fmt(grp, LOG_WARNING, fmt, ...)
 end
 
+function log_notice(grp, fmt, ...)
+	log_fmt(grp, LOG_NOTICE, fmt, ...)
+end
+
 function log_info(grp, fmt, ...)
 	log_fmt(grp, LOG_INFO, fmt, ...)
 end