Force poll the battery when showing the menu.

Making sure to always show up to date info.

Also fix the battery polling cache invalidation logic to actually
work?
Should make it behave properly on devices where we handle resuming
ourselves.

frontend/device/generic/powerd.lua

@@ -74,7 +74,8 @@ function BasePowerD:getCapacity()
 end
 
 function BasePowerD:refreshCapacity()
-    self:getCapacityHW()
+    -- We want our next getCapacity call to actually pull up to date info instead of a cached value ;)
+    self.capacity_pulled_count = self.capacity_cached_count
 end
 
 function BasePowerD:isCharging()

frontend/ui/widget/touchmenu.lua

@@ -381,6 +381,8 @@ function TouchMenu:init()
     }
 
     self.bar:switchToTab(self.last_index or 1)
+    -- Make sure we always show an up to date battery status when first opening the menu...
+    Device:getPowerDevice():refreshCapacity()
     self:updateItems()
 end