overlay app-eselect/eselect-go: Drop unused package

Incidentally, it was yet another package that was using a source code
from github.com/coreos that we forgot to fork over to Flatcar org.

sdk_container/src/third_party/coreos-overlay/app-eselect/eselect-go/Manifest

@@ -1 +0,0 @@
-DIST eselect-go-0.1.0.tar.gz 104232 BLAKE2B 770773f990509bdfcdb1c463f01915526358fe28b440be288dad0833a4e8647cf52ba136569b4e7b46c71b80c6ffd43075fd25bfb516ec5790f80067247e08c5 SHA512 b7e9bf07bc7026115d639ed893c54332d63cd2d7a46a6f3b2f8a6748658dfb82f09e875def8bf9abecfb1e39f054ef194b39b0c415ac9ce69ea03332125d4c1f

sdk_container/src/third_party/coreos-overlay/app-eselect/eselect-go/eselect-go-0.1.0-r1.ebuild

@@ -1,36 +0,0 @@
-# Copyright 2016 CoreOS, Inc.
-# Distributed under the terms of the GNU General Public License v2
-
-EAPI=8
-
-DESCRIPTION="Eselect module for managing multiple Go versions"
-HOMEPAGE="https://github.com/coreos/eselect-go"
-SRC_URI="https://github.com/coreos/eselect-go/releases/download/v${PV}/${P}.tar.gz"
-# Note for future releases: the tarball was generated via `make dist` and
-# uploaded to GitHub so there is no need for initializing autotools here.
-
-LICENSE="GPL-2"
-SLOT="0"
-KEYWORDS="amd64 arm64"
-IUSE="test"
-RESTRICT="!test? ( test )"
-
-DEPEND="test? ( dev-libs/glib )"
-RDEPEND="app-admin/eselect
-	!dev-lang/go:0"
-
-src_configure() {
-	# Go is installed to /usr/lib, not /usr/lib64
-	econf --libdir=/usr/lib
-}
-
-src_install() {
-	keepdir /etc/env.d/go
-	default
-}
-
-pkg_postinst() {
-	if has_version 'dev-lang/go'; then
-		eselect go update --if-unset
-	fi
-}

sdk_container/src/third_party/coreos-overlay/app-eselect/eselect-go/metadata.xml

@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
-<pkgmetadata>
-	<longdescription lang="en">
-		This tool is intended for use in the CoreOS SDK in order to support
-		packages or architectures that cannot upgrade to the same Go version
-		all at the same time. Gentoo doesn't support this use case.
-	</longdescription>
-	<upstream>
-		<remote-id type="github">coreos/eselect-go</remote-id>
-	</upstream>
-</pkgmetadata>