leds: rgb: leds-qcom-lpg: Add support for 6-bit PWM resolution

Currently, driver only allows for PWM modules to use 9-bit resolution.
However, PWM modules can support 6-bit and 9-bit resolution. Add support
for 6-bit resolution.

Suggested-by: Zejiong Huang <zejiongh@qti.qualcomm.com>
Signed-off-by: Anjelique Melendez <anjelique.melendez@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250213003533.1684131-1-anjelique.melendez@oss.qualcomm.com


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