[Docker-maint] Bug#784543: golang: test failures on arm64

[Edmund Grimley Evans]

Control: found -1 1.5.1-1~exp1

I tried golang_1.5.1-1~exp1 over the weekend.

Firstly, I wasn't able to bootstrap it with gccgo-5, so I'm not sure
that the "golang-go (>= 2:1.4.2-2~) | gccgo-5" in debian/control is
correct.

With golang installed, it built but there were some test failures,
though I can't guarantee my set-up wasn't somehow to blame:


--- FAIL: TestIPv4MulticastListener
        listen_test.go:556: 224.0.0.254 not found in multicast rib

--- FAIL: TestGdbPython
        runtime-gdb_test.go:42: gdb version 7.9
        runtime-gdb_test.go:129: failed to load Go runtime support:
warning: File "/usr/share/go/src/runtime/runtime-gdb.py" auto-loading
has been declined by your `auto-load safe-path' set to
"$debugdir:$datadir/auto-load:/tmp/golang/golang-1.5.1/src/runtime".

--- FAIL: TestCloneNEWUSERAndRemapNoRootDisableSetgroups
        exec_linux_test.go:53: Cmd failed with err fork/exec
/usr/bin/whoami: operation not permitted, output: