drm/lcdif: Clean up headers

Drop unneeded headers, sort rest alphabetically, no functional change.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Liu Ying <victor.liu@nxp.com>
Reported-by: Liu Ying <victor.liu@oss.nxp.com>
Tested-by: Martyn Welch <martyn.welch@collabora.com>
Fixes: 9db35bb3 ("drm: lcdif: Add support for i.MX8MP LCDIF variant")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexander Stein <alexander.stein@ew.tq-group.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Liu Ying <victor.liu@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Martyn Welch <martyn.welch@collabora.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Robby Cai <robby.cai@nxp.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stefan Agner <stefan@agner.ch>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220819140852.255187-1-marex@denx.de