cmd/golangorg: fixup -tags prod for internal/web

prod.go is build-tagged away and not updated by rf.

Change-Id: I40a655586ff9e019cccdf82ca96b25c6b80e383d
Reviewed-on: https://go-review.googlesource.com/c/website/+/317657
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
diff --git a/cmd/golangorg/prod.go b/cmd/golangorg/prod.go
index e2b8328..b156bfc 100644
--- a/cmd/golangorg/prod.go
+++ b/cmd/golangorg/prod.go
@@ -36,7 +36,7 @@
 }
 
 func lateSetup(mux *http.ServeMux) {
-	pres.GoogleAnalytics = os.Getenv("GOLANGORG_ANALYTICS")
+	site.GoogleAnalytics = os.Getenv("GOLANGORG_ANALYTICS")
 
 	datastoreClient, memcacheClient := getClients()