media: mtk-jpegdec: export jpeg decoder functions

[ Upstream commit 08d530a8 ]

mtk jpeg decoder is built as a module, export some functions to make them
visible by other modules.

Signed-off-by: kyrie wu <kyrie.wu@mediatek.com>
Signed-off-by: irui wang <irui.wang@mediatek.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Stable-dep-of: d8212c5c ("media: mtk-jpeg: Remove cancel worker in mtk_jpeg_remove to avoid the crash of multi-core JPEG devices")
Signed-off-by: Sasha Levin <sashal@kernel.org>