anv: use COMPUTE_WALKER post sync field to track compute work

This is more accurate than PIPE_CONTROL as it won't introduce stalls
between the compute dispatches.

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Felix DeGrood <felix.j.degrood@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23131>
6 files changed