Remove checks for ancient gcc/MinGW versions.

Don't test for wxUSE_NORLANDER_HEADERS, this is always true since many, many
years.

Remove tests for gcc version < 3.3, notably 2.95: the minimal supported gcc
version is 3.4.

Closes #15727.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76549 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/dialup.cpp

@@ -49,7 +49,6 @@ wxDEFINE_EVENT( wxEVT_DIALUP_DISCONNECTED, wxDialUpEvent );
 // Wine: no wininet.h
 #if (!defined(__BORLANDC__) || (__BORLANDC__>=0x550)) && \
     (!defined(__GNUWIN32__) || wxCHECK_W32API_VERSION(0, 5)) && \
-    !defined(__GNUWIN32_OLD__) && \
     !defined(__WINE__)
 
 #include <ras.h>