media: rockchip/vpu: Prepare things to support decoders

The code in rockchip_vpu_v4l2 was hardcoded for encoder support.
Modify it more generic to support the decoder case so that we can
re-use the same vb2/v4l2 ops for both devices.
Co-developed-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/staging/media/rockchip/vpu/rockchip_vpu.h

@@ -262,4 +262,10 @@ static inline u32 vepu_read(struct rockchip_vpu_dev *vpu, u32 reg)
 	return val;
 }
 
+static inline bool
+rockchip_vpu_is_encoder_ctx(const struct rockchip_vpu_ctx *ctx)
+{
+	return true;
+}
+
 #endif /* ROCKCHIP_VPU_H_ */