Revert "Fix the VCL name of directors"

This reverts commit e7d5fb68.

Apparently this change looks intentional, but it should be revisited as
it makes troubleshooting significantly harder when logs (for example
Backend_health records) aren't explicit about the backend they are
referring to.

bin/varnishd/cache/cache_backend.c

@@ -575,7 +575,7 @@ VRT_new_backend_clustered(VRT_CTX, struct vsmw_cluster *vc,
 
 	be->director = VRT_AddDirector(ctx,
 	    vbp != NULL ? vbe_methods : vbe_methods_noprobe, be,
-	    "%s.%s", VCL_Name(ctx->vcl), vrt->vcl_name);
+	    "%s", vrt->vcl_name);
 
 	if (be->director != NULL) {
 		/* for cold VCL, update initial director state */