leds: aw200xx: Make read-only array coeff_table static const

Don't populate the read-only array coeff_table on the stack at
run time, instead make it static const.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20240119232630.2752239-1-colin.i.king@gmail.com


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