runtime: add newline to "finalizer already set" error
runtime: add newline to "finalizer already set" error

R=rsc, bradfitz
CC=golang-dev
http://codereview.appspot.com/4523047

Committer: Russ Cox <5ad239cb8a44f659eaaee0aa1ea5b94947abe557@golang.org>
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go