drm/rockchip: lvds: do not print scary message when probing defer

This scary message can misled the user into thinking something bad has
happened and needs to be fixed, however it could simply be part of a
normal boot process where EPROBE_DEFER is taken into account. Therefore,
let's use dev_err_probe so that this message doesn't get shown (by
default) when the return code is EPROBE_DEFER.

Fixes: 34cc0aa2 ("drm/rockchip: Add support for Rockchip Soc LVDS")
Cc: Quentin Schulz <foss+kernel@0leil.net>
Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20231120-rk-lvds-defer-msg-v2-2-9c59a5779cf9@theobroma-systems.com