The existing device_set_power_state() API works only in synchronous
mode and this is not desirable for devices(ex: Gyro) which take
longer time (few 100 mSec) to suspend/resume.

To support async mode, a new callback argument is added to the API.
The device drivers can asynchronously suspend/resume and call the
callback function upon completion of the async request.

This commit adds the missing callback parameter to all the drivers
to make it compliant with the new API.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>

Add framework for device Idle Power Management(IPM)
for suspending devices based on device idle. This will
help in saving power even while system(CPU) is active.

The framework uses device_set_power_state() API set the
device power state accordingly based on the usage count.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>

Added test for Device Idle Power Management to invoke
device_pm_get/put API's.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>