drm/panel: Rename Sony ACX424 to Novatek NT35560

A code drop from Sony Mobile reveals that the ACX424 panels are
built around the Novatek NT35560 panel controllers so just bite
the bullet and rename the driver and all basic symbols so that
we can modify this driver to cover any other panels also using
the Novatek NT35560 display controller.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220103113822.654592-1-linus.walleij@linaro.org