cov: remove tautological #defines
cov: remove tautological #defines

R=golang-dev
CC=golang-dev, rsc
http://codereview.appspot.com/4941048

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