Device:Android: always call "_decideFrontlightState" in "setIntensityHW" (#10737)

re https://github.com/koreader/koreader/pull/10731#discussion_r1271505121

This PR changes so that androids implementation of `setIntensityHW` always calls `_decideFrontlightState`

frontend/device/android/device.lua

@@ -516,7 +516,6 @@ function Device:_showLightDialog()
     elseif action == C.ALIGHTS_DIALOG_CANCEL then
         logger.dbg("Dialog Cancel, brightness: " .. self.powerd.fl_intensity)
         self.powerd:setIntensityHW(self.powerd.fl_intensity)
-        self.powerd:_decideFrontlightState()
         if android.isWarmthDevice() then
             logger.dbg("Dialog Cancel, warmth: " .. self.powerd.fl_warmth)
             self.powerd:setWarmth(self.powerd.fl_warmth)

frontend/device/android/powerd.lua

@@ -16,6 +16,7 @@ function AndroidPowerD:setIntensityHW(intensity)
 
     self.fl_intensity = intensity
     android.setScreenBrightness(math.floor(intensity * self.bright_diff / self.fl_max))
+    self:_decideFrontlightState()
 end
 
 function AndroidPowerD:init()