drm/bridge: analogix: Do not use device's drvdata

The driver that instantiates the bridge should own the drvdata, as all
driver model callbacks (probe, remove, shutdown, PM ops, etc.) are also
owned by its driver struct. Moreover, storing two different pointer
types in driver data depending on driver initialization status is barely
a good practice and in fact has led to many bugs in this driver.

Let's clean up this mess and change Analogix entry points to simply
accept some opaque struct pointer, adjusting their users at the same
time to avoid breaking the compilation.

Signed-off-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Acked-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20180110162348.22765-2-thierry.escande@collabora.com