Fix partial HW dithered refreshes sometimes appearing to shift refreshed content (#6267)

* Fix HW dithered partial refreshes sometimes behaving as if the refreshed
content had moved a few pixels to the side...

Probably a kernel issue with the alignment fixup in the EPDC?

* Get rid of the legacy coordinates fixup

It shouldn't be necessary anymore.
And I'd rather fix the root cause, anyway.

* Bump base

(https://github.com/koreader/koreader-base/pull/1116)

* Missed a few DIVs in #6224

frontend/apps/reader/modules/readercropping.lua

@@ -112,7 +112,7 @@ function ReaderCropping:onPageCrop(mode)
         self.ui:handleEvent(Event:new("SetZoomMode", "page", "cropping"))
     end
     self.ui:handleEvent(Event:new("SetDimensions",
-        Geom:new{w = Screen:getWidth(), h = Screen:getHeight()*11/12})
+        Geom:new{w = Screen:getWidth(), h = math.floor(Screen:getHeight()*11/12)})
     )
     self.bbox_widget = BBoxWidget:new{
         crop = self,