r600/sfn: Use dependecies to order barriers and LDS/RAT instructions
This gives more freedom to schedule the group barrier and removes the need to add blocks around a barrier to keep the scheduler in check. This should avoid emitting some CF instructions. Closes: #11002 Fixes: fe881bf0 r600/sfn: move kill handling fully to scheduling v2: grammar fixes (lorn10) Signed-off-by:Gert Wollny <gert.wollny@collabora.com> Part-of: <!28840>