On my machine, a guest fails to boot if it has a sound card, but not
graphical device/display is configured, because pulseaudio fails to
initialize since it can't access $HOME.
A workaround is removing the audio device, however on ARM boards there
isn't any option to do that, so -nographic always fails.
Set QEMU_AUDIO_DRV=none if no <graphics> are configured. Unfortunately
this has massive test suite fallout.
Add a qemu.conf parameter nographics_allow_host_audio, that if enabled
will pass through QEMU_AUDIO_DRV from sysconfig (similar to
vnc_allow_host_audio)
Code that validates the whitelist for the RNG device filename
didn't account for fact that filename may be NULL. This led
to a NULL reference crash. This wasn't caught since the test
suite was not covering this XML syntax
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>