Remove stub spell checking functions from wxiOS wxTextCtrl

There doesn't seem to be any need to have these functions here as the
base class implementation already does exactly the same thing (i.e.
nothing at all).

include/wx/osx/iphone/private/textimpl.h

@@ -71,11 +71,6 @@ public:
 
     virtual bool HasOwnContextMenu() const { return true; }
 
-#if wxUSE_SPELLCHECK
-    virtual void CheckSpelling(const wxTextProofOptions& options);
-    virtual bool IsSpellingCheckEnabled() const;
-#endif // wxUSE_SPELLCHECK
-
     virtual wxSize GetBestSize() const;
 
 protected:

src/osx/iphone/textctrl.mm

@@ -500,19 +500,6 @@ void wxUITextViewControl::SetStyle(long start,
     }
 }
 
-#if wxUSE_SPELLCHECK
-
-void wxUITextViewControl::CheckSpelling(const wxTextProofOptions& WXUNUSED(options))
-{
-}
-
-bool wxUITextViewControl::IsSpellingCheckEnabled() const
-{
-    return false;
-}
-
-#endif // wxUSE_SPELLCHECK
-
 wxSize wxUITextViewControl::GetBestSize() const
 {
     wxRect r;