Bump liberty, check the connection while searching

This just prevents immediate assertion failures.

liberty

@@ -1 +1 @@
-Subproject commit 75fc6f1c374796f9e794297c3893089009b8772f
+Subproject commit 017cb1d5702a32603810545cd74c1da65e35d12d

nncmpp.c

@@ -3785,6 +3785,8 @@ static void
 search_on_changed (void)
 {
 	struct mpd_client *c = &g.client;
+	if (c->state != MPD_CONNECTED)
+		return;
 
 	size_t len;
 	char *u8 = (char *) u32_to_u8 (g.editor.line, g.editor.len + 1, NULL, &len);