nocturne: Enable low power idle
nocturne: Enable low power idle

BUG=b:112037915
TEST=25mW lower in s0ix

Change-Id: Ie7e6c3e3d1372f64730d322864e4315afdf7c2e6
Signed-off-by: Puthikorn Voravootivat <6b0bf59b07ec88a47755d311f85101e4220afc86@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1178973
Reviewed-by: Aseda Aboagye <12c9b286316a940fd31c24070da5ab64cdd4d0e7@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec