[ Upstream commit c974ac77 ]

If a child device like touchscreen is wakeup capable, then keep ADC
interface on, so that a touching resistive screen will generate wakeup
event to the system.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>