leds: lp5521: Add an error check in lp5521_post_init_device

lp55xx_write() can return an error code, add a check for this.

Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20231020091930.207870-1-suhui@nfschina.com
Signed-off-by: Lee Jones <lee@kernel.org>