drm/panel: p079zca: Use of_device_get_match_data()

Use this helper to get rid of some extra boilerplate code.

Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180710110127.12315-1-thierry.reding@gmail.com