Previously, #:imported-modules was ignored, causing cross-compilation
failures. This bug seems seems to have been introduced in
e37dcf63dcea0817ffd74722ee5ff2d103aa2157.
After this commit, there remain other cross-compilation problems,
e.g. <https://issues.guix.gnu.org/51981> fixes one of them.
* guix/build-system/go.scm (go-cross-build)[builder]: Wrap in
with-imported-modules.
Signed-off-by: Ludovic Courtès <ludo@gnu.org>