eclass/go-module.eclass: upgrade to upstream

Imports the file from upstream Gentoo Linux commit
a8173fa13680333b65751046fea0ad807b741cfa .

This is needed for enabling app-admin/google-osconfig-agent in
src/overlay/overlay-lakitu .

BUG=b:152434359
TEST=See the following commit.

Cq-Depend: chromium:2266239
Change-Id: I9c0996e501b4dd107a66ca2c8fc6892600c4e45e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2266238
Tested-by: Edward Jee <edjee@google.com>
Auto-Submit: Edward Jee <edjee@google.com>
Reviewed-by: Tom Hughes <tomhughes@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Edward Jee <edjee@google.com>
1 file changed