refresh libusual

diff --git a/lib b/lib
index 0c3aba53cf6105acbf4a82b73ae4143afae3c249..4235e02ac2cd3218ec53b3fd6eadbc1894eef250 160000 (submodule)
--- a/lib
+++ b/lib
@@ -1 +1 @@
-Subproject commit 0c3aba53cf6105acbf4a82b73ae4143afae3c249
+Subproject commit 4235e02ac2cd3218ec53b3fd6eadbc1894eef250