Fix apparently broken OSL_ASSERT (that would have never fired)

Change-Id: I5db308219aab173c5ed27c2f61908472aa1b697e

sd/source/core/drawdoc3.cxx

@@ -1454,7 +1454,7 @@ void SdDrawDocument::SetMasterPage(sal_uInt16 nSdPageNum,
             {
                 delete pNewNotesMaster;
                 delete pNewMaster;
-                OSL_ASSERT("SdDrawDocument::SetMasterPage() cloning of MasterPage/NoteAmsterPage failed!" );
+                OSL_FAIL("SdDrawDocument::SetMasterPage() cloning of MasterPage/NoteAmsterPage failed!" );
                 return;
             }