drm/nouveau/dma/tu104: initial support

Appears to be compatible with GV100.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvkm/engine/device/base.c

@@ -2456,6 +2456,7 @@ nv164_chipset = {
 	.therm = gp100_therm_new,
 	.timer = gk20a_timer_new,
 	.top = gk104_top_new,
+	.dma = gv100_dma_new,
 };
 
 static int