Unbreak battery status refresh on resume on Kindle

Went kaput w/ #1854

frontend/device/generic/device.lua

@@ -104,6 +104,7 @@ function Device:outofScreenSaver()
         if self:needsScreenRefreshAfterResume() then
             self.screen:refreshFull()
         end
+        self.powerd:refreshCapacity()
     end
     self.screen_saver_mode = false
 end
@@ -169,6 +170,7 @@ function Device:usbPlugOut()
         util.usleep(1500000)
         self.screen:restoreFromSavedBB()
         self.screen:refreshFull()
+        self.powerd:refreshCapacity()
     end
 
     --@TODO signal filemanager for file changes  13.06 2012 (houqp)