Fix uses of wxDEPRECATED in WXWIN_COMPATIBILITY_2_8-only code

wxDEPRECATED must be used for the entire declaration to really work,
but this wasn't the case for a few functions (and one typedef) guarded
by WXWIN_COMPATIBILITY_2_8, resulting in gcc -Wattributes warning about
the attribute being ignored and the declaration not being really marked
as deprecated.

Fix this by applying the deprecation macro to the entire declaration,
which works well for gcc and should hopefully work for MSVC too.

include/wx/image.h

@@ -645,14 +645,14 @@ public:
         }
     )
 
-    static wxDEPRECATED(
+    wxDEPRECATED(static
         wxImageHandler *FindHandler(const wxString& ext, long type)
         {
             return FindHandler(ext, (wxBitmapType)type);
         }
     )
 
-    static wxDEPRECATED(
+    wxDEPRECATED(static
         wxImageHandler *FindHandler(long imageType)
         {
             return FindHandler((wxBitmapType)imageType);