work around BZ1099206 (go get is broken on fresh install)

Fedora golang packages are broken on fresh install
and must be reinstalled for `go get` to work.

On a fresh installation of Fedora 20 with `golang-1.2.2-7.fc20.x86_64`
or Fedora Rawhide with `golang-1.3rc1-1.fc21.x86_64`,
`go get` errors out with:

    go install runtime/cgo: open /usr/lib/golang/pkg/linux_amd64/runtime/cgo.a: permission denied

If you run `yum -y reinstall golang golang-pkg* golang-src`,
the `go get` command finishes successfully.
One should not have to reinstall the packages to get a working set.

See https://github.com/jumanjiman/bz1099206 for reproducer.