gnu: guile-lib: Fix cross compilation.

gnu: guile-lib: Fix cross compilation.

These changes were sent upstream as
https://lists.gnu.org/archive/html/guile-devel/2021-02/msg00004.html

Without this change, the .go files are built for the host architecture, rather
than the target. I noticed this when cross building the
guix-build-coordinator (for which guile-lib is an input) to the Hurd.

* gnu/packages/guile-xyz.scm (guile-lib)[arguments]: Add
'patch-for-cross-compilation phase.
[native-inputs]: Add autoconf, automake and gettext.
(guile2.0-lib): Adjust to use alist-replace.
(guile2.2-lib): Adjust to use alist-replace.