anv/video: void cast array we intentionally read off the end of

Coverity notices we're reading off the end of the array here, which is
true. We also intend to do that because we want to read the next field as
well. Cast to a `void *` to help Coverity out.

CID: 1649593
Reviewed-by: Hyunjun Ko <zzoon@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38437>

src/intel/vulkan/anv_video.c

@@ -1271,7 +1271,7 @@ vp9_prob_buf_update(struct anv_video_session *vid,
              sizeof(ctx.seg_tree_probs));
       memcpy(ctx.seg_pred_probs, seg->segmentation_pred_prob,
              sizeof(ctx.seg_pred_probs));
-      memcpy(ptr + SEG_PROBS_OFFSET, &ctx.seg_tree_probs,
+      memcpy(ptr + SEG_PROBS_OFFSET, (void *)&ctx.seg_tree_probs,
              SEG_TREE_PROBS + PREDICTION_PROBS);
    } else if (BITSET_TEST(vid->prob_tbl_set, 3)) {
       VP9_CTX_DEFAULT(seg_tree_probs);