leds: aw2013_led: use PM suspend/resume for aw2013_led

Fb notifier will call led suspend/resume function when turn
off/on screen, which is not expected because we need call
suspend when system get XO shut down and call resume when AP
wakeup. L6/L17 will be disabled in suspend if there is no RGB
led blink/glow.

Change-Id: If83b55603d29e29434af4beff535a606e32fdd24
Signed-off-by: Mao Li <maol@codeaurora.org>