Snapcraft fails to strip go binaries on arm

This is the snapcraft part

```
  mdns-publisher:
    plugin: go
    go-packages: [github.com/kyrofa/mdns-publisher]
```

and this is the result when bulding for arm on Launchpad

```
Stripping mdns-publisher
Command '['/bin/sh', '/tmp/tmpoey0zv3q', 'ldd', b'/build/owncloud-
snap/snap/bin/mdns-publisher']' returned non-zero exit status 1
Traceback (most recent call last):
  File "/usr/share/launchpad-buildd/slavebin/buildsnap", line 195, in main
    builder.build()
  File "/usr/share/launchpad-buildd/slavebin/buildsnap", line 141, in build
    ["snapcraft"], path=os.path.join("/build", self.name))
  File "/usr/share/launchpad-buildd/slavebin/buildsnap", line 92, in run_build_command
    self.chroot(["/bin/sh", "-c", command], echo=echo)
  File "/usr/share/launchpad-buildd/slavebin/buildsnap", line 66, in chroot
    "/usr/bin/sudo", "/usr/sbin/chroot", self.chroot_path] + args)
  File "/usr/lib/python2.7/subprocess.py", line 540, in check_call
    raise CalledProcessError(retcode, cmd)
CalledProcessError: Command '['/usr/bin/sudo', '/usr/sbin/chroot', '/home/buildd/build-SNAPBUILD-541/chroot-autobuild', 'linux32', '/bin/sh', '-c', 'cd /build/owncloud-snap && env LANG=C.UTF-8 snapcraft']' returned non-zero exit status 1
```

Works fine when compiling locally on amd64