drm/nouveau/gpio: send separate event types for high/low transitions

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --cc drivers/gpu/drm/nouveau/core/include/subdev/gpio.h
Simple merge

diff --cc drivers/gpu/drm/nouveau/core/subdev/gpio/base.c
Simple merge

diff --cc drivers/gpu/drm/nouveau/core/subdev/gpio/priv.h
Simple merge

diff --cc drivers/gpu/drm/nouveau/nouveau_connector.c
Simple merge