[fix] Allow closing SortWidget (#6464)

For now, close on any keypress.

Cf. https://github.com/koreader/koreader/issues/6463

frontend/ui/widget/sortwidget.lua

@@ -168,6 +168,13 @@ function SortWidget:init()
         w = self.width or Screen:getWidth(),
         h = self.height or Screen:getHeight(),
     }
+    if Device:hasKeys() then
+        self.key_events = {
+            --don't get locked in on non touch devices
+            AnyKeyPressed = { { Device.input.group.Any },
+                seqtext = "any key", doc = "close dialog" }
+        }
+    end
     if Device:isTouchDevice() then
         self.ges_events.Swipe = {
             GestureRange:new{
@@ -455,6 +462,10 @@ function SortWidget:swapItems(pos1, pos2)
     end
 end
 
+function SortWidget:onAnyKeyPressed()
+    return self:onClose()
+end
+
 function SortWidget:onNextPage()
     self:nextPage()
     return true