[master] ce3dbbed2 Assert that VRBT_INSERT did not find the element to insert

[Nils Goroll]

commit ce3dbbed23749d1585f3da5b32063b8b746f9f42
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Mon Jan 11 16:08:58 2021 +0100

    Assert that VRBT_INSERT did not find the element to insert
    
    just to clarify for the next commit.

diff --git a/bin/varnishd/cache/cache_vrt_priv.c b/bin/varnishd/cache/cache_vrt_priv.c
index 1685ec06e..059392386 100644
--- a/bin/varnishd/cache/cache_vrt_priv.c
+++ b/bin/varnishd/cache/cache_vrt_priv.c
@@ -152,7 +152,7 @@ vrt_priv_dynamic(struct ws *ws, struct vrt_privs *privs, uintptr_t vmod_id)
 		return (NULL);
 	INIT_OBJ(vp, VRT_PRIV_MAGIC);
 	vp->vmod_id = vmod_id;
-	VRBT_INSERT(vrt_privs, privs, vp);
+	AZ(VRBT_INSERT(vrt_privs, privs, vp));
 	return (vp->priv);
 }