gnu: Remove go-github-com-mtibben-androiddnsfix.

Not in use by any other packages in Guix, it was a temporary solution
implemented 5 years ago according to project's about field:
"androiddnsfix is a hack around the issues in
<https://github.com/golang/go/issues/8877>"

* gnu/packages/golang.scm
(go-github-com-mtibben-androiddnsfix, go-github-com-androiddnsfix):
Delete variables.

Change-Id: Ie2fda123b03b1cf99c70b39198eaabfe3e6baa8f

gnu/packages/golang.scm

@@ -3873,36 +3873,6 @@ (define-public go-github-com-gsterjov-go-libsecret
 @code{Secret Service} DBus interface.")
     (license license:expat)))
 
-(define-public go-github-com-mtibben-androiddnsfix
-  (let ((commit "ff02804463540c36e3a148dcf4b009d003cf2a31")
-        (revision "0"))
-    (package
-      (name "go-github-com-mtibben-androiddnsfix")
-      (version (git-version "0.0.0" revision commit))
-      (source (origin
-                (method git-fetch)
-                (uri (git-reference
-                      (url "https://github.com/mtibben/androiddnsfix")
-                      (commit commit)))
-                (file-name (git-file-name name version))
-                (sha256
-                 (base32
-                  "1pcbjs793kd0yg3dcp79agfxm7xm3sldx2r7v66ipzpcq0j2npi2"))))
-      (build-system go-build-system)
-      (arguments
-       '(#:import-path "github.com/mtibben/androiddnsfix"
-         #:phases %standard-phases))
-      (synopsis "Work around lack of @file{/etc/resolv.conf} on Android")
-      (description
-       "This package allows Go applications to work around lack of
-@file{/etc/resolv.conf} on Android, as described in
-@url{https://github.com/golang/go/issues/8877}.")
-      (home-page "https://github.com/mtibben/androiddnsfix")
-      (license license:expat))))
-
-(define-public go-github-com-androiddnsfix
-  (deprecated-package "go-github-com-androiddnsfix" go-github-com-mtibben-androiddnsfix))
-
 (define-public go-github-com-go-ini-ini
   (package
     (name "go-github-com-go-ini-ini")