anv: bail out if anv_wsi_init() fails

anv: bail out if anv_wsi_init() fails

Otherwise we'll end up setting up a device with no winsys integration.

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
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Hard-coding the rendernode name in anv_physical_device_init() is a bad
idea really. We could/should be using drmGetDevices() to get info on all
the devices (master/render/etc. node names, pci location etc.) and apply
our heuristics on top of that.

That can come up as a follow up change.