PNP: convert PNP driver bus legacy pm_ops to dev_pm_ops

Convert drivers/pnp/driver.c bus legacy pm_ops to dev_pm_ops using
existing suspend and resume routines.  Add freeze interface to
handle PM_EVENT_FREEZE correctly with dev_pm_ops.  pm_op() looks for
freeze interface when the event is PM_EVENT_FREEZE.

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>