Avoid implicitly declared members of EDITENG_DLLPUBLIC class

...implicit definitions of which, under the MSVC ABI, would need to be emitted
into every editeng .cxx that happens to include this file, but which would fail
for the

  VclPtr<vcl::Window> pWin;

member wherever vcl::Window happens to be incomplete.

Change-Id: I0a1cc61af086f3a3235a995c34834bc131531b84

include/editeng/splwrap.hxx

@@ -71,6 +71,9 @@ private:
     EDITENG_DLLPRIVATE bool     SpellNext();        // select next area
     bool    FindSpellError();   // Check for errors (over areas)
 
+    SvxSpellWrapper(SvxSpellWrapper const &) = delete;
+    void operator =(SvxSpellWrapper const &) = delete;
+
 public:
     SvxSpellWrapper( vcl::Window* pWn,
                      css::uno::Reference< css::linguistic2::XSpellChecker1 >  &xSpellChecker,