panfrost: Fix fence leak
When overwriting the writer, we need to release the old reference. Signed-off-by:Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Reviewed-by:
Boris Brezillon <boris.brezillon@collabora.com> Fixes: 2dad9fde ("panfrost: Start tracking inter-batch dependencies") Cc: mesa-stable Part-of: <mesa/mesa!5859> (cherry picked from commit 20dd3702)