vty: Fix osmo_tdef timers not listed in write config

Change-Id: I5c7ae18919e4b016505aa01eea6694d8a3f5df5f
diff --git a/src/pcu_vty.c b/src/pcu_vty.c
index 6592cae..c47c896 100644
--- a/src/pcu_vty.c
+++ b/src/pcu_vty.c
@@ -271,6 +271,8 @@
 	else
 		vty_out(vty, " gb-dialect classic%s", VTY_NEWLINE);
 
+	osmo_tdef_vty_write(vty, bts->T_defs_pcu, " timer ");
+
 	return CMD_SUCCESS;
 }