no bytes pushed from vdp _fini

in the varnish-cache variant of the code this works because not VDP_Push
is used but the internal push to the parent

src/foreign/cache_esi_deliver.c

@@ -316,11 +316,11 @@ vped_gzgz_fini(struct req *req, void **priv)
 	uint32_t ilen;
 	struct vped_gzgz_priv *vgzgz;
 
+	(void) req;
+
 	CAST_OBJ_NOTNULL(vgzgz, *priv, VPED_GZGZ_PRIV_MAGIC);
 	*priv = NULL;
 
-	(void)VDP_bytes(req, VDP_FLUSH, NULL, 0);
-
 	icrc = vle32dec(vgzgz->tailbuf);
 	ilen = vle32dec(vgzgz->tailbuf + 4);
 	vgzgz->gz->crc = crc32_combine(vgzgz->gz->crc, icrc, ilen);