ci: Don't forget to set NIR_VALIDATE in baremetal runs.

ci: Don't forget to set NIR_VALIDATE in baremetal runs.

Given that a530 doesn't have cpufreq, we really don't have the time to be
running the validator on all of deqp.  This also helps explain why I had
to go to such a small fraction on the a3xx gles3 run (which we can now
increase).  However, a3xx gles2 seems to be fast enough that we can leave
it enabled and get coverage for older chips.

Because we run more tests now, clear out some stale xfails from the a3xx
list.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5089>