radv/ci: only reboot on hangs for vkcts-navi10-valve

radv/ci: only reboot on hangs for vkcts-navi10-valve

vkcts-navi10-valve has the nasty habit on hanging the GPU, so we
introduced an auto-retry... but for every radv job. Let's stop doing
that, and instead limit the auto-retry to vkcts-navi10-valve only.

Additionally, let's increase the number of attempts to 3 (2 retries),
as sometimes, it may still fail and we don't want to flag it as a
fail in nightly runs.

Let's hope we'll get to the bottom of this hang sooner rather than
later, so that we can remove this hack!

Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Martin Roukala (né Peres) <martin.roukala@mupuf.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22596>