asn1: fix incorrect prints found by govet
asn1: fix incorrect prints found by govet

R=golang-dev
CC=golang-dev
http://codereview.appspot.com/5449063

Committer: Adam Langley <db68fba232b2c49ed3e9d3081df349dde7b61dfd@golang.org>
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go