ACPI / PM: Move device power management functions to device_pm.c

Move ACPI device power management functions from drivers/acpi/bus.c
to drivers/acpi/device_pm.c.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/internal.h

@@ -61,7 +61,6 @@ int acpi_device_sleep_wake(struct acpi_device *dev,
 int acpi_power_get_inferred_state(struct acpi_device *device, int *state);
 int acpi_power_on_resources(struct acpi_device *device, int state);
 int acpi_power_transition(struct acpi_device *device, int state);
-int acpi_bus_init_power(struct acpi_device *device);
 
 int acpi_wakeup_device_init(void);
 void acpi_early_processor_set_pdc(void);