removed overloaded virtual InitWith() methods, keep just a single InitRGBA()

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@41123 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/colour.cpp

@@ -77,7 +77,8 @@ wxColour::~wxColour()
 {
 }
 
-void wxColour::InitWith(unsigned char r, unsigned char g, unsigned char b)
+void wxColour::InitRGBA(unsigned char r, unsigned char g, unsigned char b,
+                        unsigned char WXUNUSED(a))
 {
     m_red = r;
     m_green = g;