backlight: lms501kf03: Remove unnecessary include of <linux/backlight.h>

This lcd driver is independent from the backlight code.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20240906075439.98476-13-tzimmermann@suse.de


Signed-off-by: Lee Jones <lee@kernel.org>