ACPI / fan: use acpi_device_xxx_power instead of acpi_bus equivelant

When we have the acpi_device pointer, there is no need to pass the
device's handle to the acpi_bus_xxx_power functions to get/set/update
the device's power state, instead, use the acpi_device_xxx_power
functions directly.

To make this happen for fan module, export acpi_device_update_power.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>