va/x11: Don't crash the application if it does not have access to the DRI2 device.
va/x11: Don't crash the application if it does not have access to the DRI2 device.

Applications run in a different account than the logged in user will not have permission
to access /dev/dri/card0 but may be able to work without it, particularly if VA-API was
brought in through a general framework such as GStreamer.

Signed-off-by: Francois Gouget <6b915da68578f6eb004fe99432b967565fc9be8f@free.fr>

gbeauchesne/libva,gbeauchesne/libva,gbeauchesne/libva