There are no more users left of the gpd_dev_ops.active_wakeup()
callback.  All have been converted to GENPD_FLAG_ACTIVE_WAKEUP.
Hence remove the callback.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NKevin Hilman <khilman@baylibre.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>