vrend: Always fallback to GL if a GBM transfer fails
This completes the fix in 6a285a1f vrend: When the GBM upload code path fails, fall back to use OpenGL
Due to an influx of spam, we have had to impose restrictions on new accounts. Please see this wiki page for instructions on how to get full permissions. Sorry for the inconvenience.
This completes the fix in 6a285a1f vrend: When the GBM upload code path fails, fall back to use OpenGL