CLEANUP: haproxy: Free post_proxy_check_list in deinit()

This allocation is technically always reachable and cannot leak, but so are
a few others that *are* freed.
diff --git a/src/haproxy.c b/src/haproxy.c
index 663922e..b017070 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -2403,6 +2403,7 @@
 	struct proxy_deinit_fct *pxdf, *pxdfb;
 	struct server_deinit_fct *srvdf, *srvdfb;
 	struct post_server_check_fct *pscf, *pscfb;
+	struct post_proxy_check_fct *ppcf, *ppcfb;
 
 	deinit_signals();
 	while (p) {
@@ -2722,6 +2723,11 @@
 		free(pscf);
 	}
 
+	list_for_each_entry_safe(ppcf, ppcfb, &post_proxy_check_list, list) {
+		LIST_DEL(&ppcf->list);
+		free(ppcf);
+	}
+
 	vars_prune(&global.vars, NULL, NULL);
 	pool_destroy_all();
 	deinit_pollers();