Don't use DLL export declaration with wxTextProofOptions

This class doesn't have any non-inline methods, so applying DLL export
declaration to it is at best useless and might even be harmful, so don't
do it.

include/wx/textctrl.h

@@ -133,7 +133,7 @@ enum wxTextCtrlHitTestResult
 // Passed to ::EnableProofCheck() to configure the proofing options for
 // this control
 // ----------------------------------------------------------------------------
-class WXDLLIMPEXP_CORE wxTextProofOptions
+class wxTextProofOptions
 {
 public:
     wxTextProofOptions(const wxString& lang = wxEmptyString)