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/ui/widget/infomessage.lua

@@ -107,7 +107,7 @@ function InfoMessage:init()
 
     local text_width
     if self.width == nil then
-        text_width = Screen:getWidth() * 2 / 3
+        text_width = math.floor(Screen:getWidth() * 2/3)
     else
         text_width = self.width - image_widget:getSize().w
         if text_width < 0 then