drm/i915: stop using ttm_bo_wait

TTM is just wrapping core DMA functionality here, remove the mid-layer.
No functional change.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221125102137.1801-7-christian.koenig@amd.com

drivers/gpu/drm/i915/gem/i915_gem_ttm.c

@@ -599,13 +599,16 @@ i915_ttm_resource_get_st(struct drm_i915_gem_object *obj,
 static int i915_ttm_truncate(struct drm_i915_gem_object *obj)
 {
 	struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
-	int err;
+	long err;
 
 	WARN_ON_ONCE(obj->mm.madv == I915_MADV_WILLNEED);
 
-	err = ttm_bo_wait(bo, true, false);
-	if (err)
+	err = dma_resv_wait_timeout(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP,
+				    true, 15 * HZ);
+	if (err < 0)
 		return err;
+	if (err == 0)
+		return -EBUSY;
 
 	err = i915_ttm_move_notify(bo);
 	if (err)