Hangs to build on ppc64el

It seems impossible to get ppc64el build to finish on yakkety. The build seems to fail but hangs forever (until cancelling the build job) probably because there's a test related thread loose and not killed.

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gdk_pixbuf-2.0 -lapparmor -Wl,-rpath,/<<BUILDDIR>>/content-hub-0.2+16.10.20160830/build/src/com/ubuntu/content:
make[3]: Leaving directory '/<<BUILDDIR>>/content-hub-0.2+16.10.20160830/build'
[100%] Built target content-hub-send
make[2]: Leaving directory '/<<BUILDDIR>>/content-hub-0.2+16.10.20160830/build'
/usr/bin/cmake -E cmake_progress_start /<<BUILDDIR>>/content-hub-0.2+16.10.20160830/build/CMakeFiles 0
make[1]: Leaving directory '/<<BUILDDIR>>/content-hub-0.2+16.10.20160830/build'
   debian/rules override_dh_auto_test
make[1]: Entering directory '/<<BUILDDIR>>/content-hub-0.2+16.10.20160830'
dbus-test-runner -t make -p "-C" -p "build/tests/acceptance-tests" -p test
DBus daemon: unix:abstract=/tmp/dbus-O9sC0cCtE9,guid=19a0b33017166ee2a4c9d4ff57cec6e9
task-0: Started with PID: 11044
task-0: make[2]: Entering directory '/<<BUILDDIR>>/content-hub-0.2+16.10.20160830/build/tests/acceptance-tests'
task-0: Running tests...
task-0: /usr/bin/ctest --force-new-ctest-process
task-0: Test project /<<BUILDDIR>>/content-hub-0.2+16.10.20160830/build/tests/acceptance-tests
task-0: Start 1: app_hub_communication_default_source
task-0: 1/10 Test #1: app_hub_communication_default_source ... Passed 0.03 sec
task-0: Start 2: app_hub_communication_known_sources
task-0: 2/10 Test #2: app_hub_communication_known_sources .... Passed 0.03 sec
task-0: Start 3: app_hub_communication_stores

** (dbus-test-runner:11039): WARNING **: Timing out at maximum wait of 30 seconds.

(dbus-test-runner:11039): libdbustest-CRITICAL **: dbus_test_service_run: assertion 'all_tasks(service, all_tasks_finished_helper, NULL)' failed
task-0: Shutting down
DBus daemon: Shutdown
debian/rules:15: recipe for target 'override_dh_auto_test' failed
make[1]: *** [override_dh_auto_test] Error 255
make[1]: Leaving directory '/<<BUILDDIR>>/content-hub-0.2+16.10.20160830'
debian/rules:7: recipe for target 'build-arch' failed
make: *** [build-arch] Error 2
dpkg-buildpackage: error: debian/rules build-arch gave error exit status 2

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This happens despite 5+ retries. Also i386 and armhf needed a retry but they did eventually finish.

This prevents getting any content-hub landing to yakkety properly.