tdf#95977: fix fly positioning regression from 0c5cbcd7

Change-Id: I7e11c7072ba0ec82237985da79f8572fdda05778
Reviewed-on: https://gerrit.libreoffice.org/23428Reviewed-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>
Tested-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>

sw/source/core/layout/flycnt.cxx

@@ -1220,7 +1220,7 @@ void SwFlyAtContentFrame::SetAbsPos( const Point &rNew )
             nY -= pCnt->GetUpperSpaceAmountConsideredForPrevFrameAndPageGrid();
         }
         else
-            nY = rNew.Y() - pCnt->Frame().Top() + pCnt->GetUpperSpaceAmountConsideredForPrevFrameAndPageGrid();
+            nY = rNew.Y() - pCnt->Frame().Top() - pCnt->GetUpperSpaceAmountConsideredForPrevFrameAndPageGrid();
     }
     else
     {