media: mediatek: vcodec: Fix encoder access NULL pointer

Need to set the private data with encoder device, or will access
NULL pointer in encoder handler.

Fixes: 1972e324 ("media: mediatek: vcodec: Fix possible invalid memory access for encoder")
Signed-off-by: Irui Wang <irui.wang@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c

@@ -138,7 +138,8 @@ int vpu_enc_init(struct venc_vpu_inst *vpu)
 	vpu->ctx->vpu_inst = vpu;
 
 	status = mtk_vcodec_fw_ipi_register(vpu->ctx->dev->fw_handler, vpu->id,
-					    vpu_enc_ipi_handler, "venc", NULL);
+					    vpu_enc_ipi_handler, "venc",
+					    vpu->ctx->dev);
 
 	if (status) {
 		mtk_venc_err(vpu->ctx, "vpu_ipi_register fail %d", status);