leds: qcom-lpg: Consistenly use dev_err_probe() in .probe()'s error path

One error path already used dev_err_probe(). Adapt the other error paths
that emit an error message to also use this function for consistency and
slightly simplified code.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231126095230.683204-3-u.kleine-koenig@pengutronix.de


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