panfrost: Fix major flaw in BO cache
BOs in the cache are chronological, so we try oldest BOs first. That means if we find the oldest BO is busy, likely every BO is busy, and we should bail early. This dramatically reduces the useless cycles spent in bo_wait. I studied the BO cache of the following drivers, all of which handle this correctly: iris, lima, etnaviv, freedreno, vc4, v3d, v3dv. Signed-off-by:Alyssa Rosenzweig <alyssa@collabora.com> Cc: mesa-stable Part-of: <mesa/mesa!10794> (cherry picked from commit 77d04989)