env.bash: Check for presence of make/gmake
env.bash: Check for presence of make/gmake

Without this, a missing gmake will result in bogus error "Did not find
Go environment variables".

R=golang-dev, rsc
CC=golang-dev
http://codereview.appspot.com/5369066

Committer: Russ Cox <5ad239cb8a44f659eaaee0aa1ea5b94947abe557@golang.org>

tav/go,tav/go,tav/go,tav/go,tav/go,tav/go,tav/go