mesa: don't share reset status across contexts

mesa: don't share reset status across contexts

If Driver.GetGraphicsResetStatus exists for one context, other contexts
will be able to use it; so there's no need to inherit reset status from
the other contexts.

This also prevented implementing the spec correctly: we're supposed to
report GL_NO_ERROR when the reset is completed (after reporting GL_*_RESET
at least once):

    If a reset status other than NO_ERROR is returned and subsequent
    calls return NO_ERROR, the context reset was encountered and
    completed. If a reset status is repeatedly returned, the context may
    be in the process of resetting.

With the existing code, the contexts will report INNOCENT_CONTEXT_RESET
forever.

Reviewed-by: André Almeida <andrealmeid@igalia.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22290>