kobo: move reader setting outside of nicke_conf module

frontend/device/kobo/nickel_conf.lua

@@ -130,9 +130,6 @@ end
 function NickelConf.frontLightLevel.set(new_intensity)
     assert(new_intensity >= 0 and new_intensity <= 100,
            "Wrong brightness value given!")
-    -- Make sure we're in sync with KOReader on the config level, too
-    G_reader_settings:saveSetting("frontlight_intensity",
-                                              new_intensity)
     return NickelConf._write_kobo_conf(re_FrontLightLevel,
                                        front_light_level_str,
                                        new_intensity)

frontend/device/kobo/powerd.lua

@@ -55,6 +55,8 @@ end
 function KoboPowerD:setIntensityHW()
     if self.fl ~= nil then
         self.fl:setBrightness(self.fl_intensity)
+        -- Make sure we persist intensity config in reader setting
+        G_reader_settings:saveSetting("frontlight_intensity", new_intensity)
         if KOBO_SYNC_BRIGHTNESS_WITH_NICKEL then
             NickelConf.frontLightLevel.set(self.fl_intensity)
         end