leds: leds-qti-tri-led: Add LED driver for QTI TRI_LED module

QTI TRI_LED module has 3 current sinks at max for LED driver and
each is controlled by a PWM channel used for LED dimming or blinking.

From msm-4.9

Change-Id: I65f33f5a95cc792ed756deb2bd4898599997ac83
4 files changed