radeonsi: update the DMA perf test

- don't test 2 waves/SA
- create the compute shader only once per subtest
- use only 1 TIME_ELAPSED query per subtest
- don't invalidate sL0 (it's not used)
- don't invalidate L2 for L2_LRU to test L2 throughput
- don't flush the CS after every run
- remove unused min/max computation

Acked-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7055>
1 file changed