vrend: add meson option to treat gl errors as non-fatal
Treating all GL errors as fatal has lead to several unexpected production breakages, where ignored errors were otherwise non-disruptive. For the short-term, we need an option to disable fatal error checking, while figuring out a long-term plan for mitigating production breakages. Signed-off-by: Ryan Neph <ryanneph@google.com> Part-of: <!836>