backport !30510 to 24.1
What does this MR do and why?
radeonsi/vcn: Add decode DPB buffers as CS dependency
This is needed to ensure correct synchronization in kernel eg. when it
moves the buffers between VRAM and GTT.
Reviewed-by: Boyuan Zhang <Boyuan.Zhang@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30510>
(cherry picked from commit 0c024bbe641b092bbbc751baae54a37642794de0)
This required a small change to make it build for 24.1.
cc @eric