Revert "drivers/video/backlight/platform_lcd.c: add support for device tree based probe"

This reverts commit 52e84243

.

The DT support never would have worked because there's no platform_data
providing ops. There's not any documented binding for it either.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220629210024.815761-1-robh@kernel.org