Allow disabling SetProcessDPIAware() call

Add Windows-specific wxMSWDisableSettingHighDPIAware() function then can
be called before startup (i.e. wxEntry() call) to disable wxWidgets'
handling of DPI awareness. This is useful for code embedded in non-wx
applications as well as for purely wx application that are not
HiDPI-ready (although the latter has the option of forcing
dpiAware=false in the manifest).

See also https://groups.google.com/d/msg/wx-dev/Z0VpgzCY34U/f1FfPqGDppMJ
and #16116.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@78406 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/init.h

@@ -30,6 +30,10 @@
     typedef char *wxCmdLineArgType;
 #endif
 
+// Call this function to prevent wxMSW from calling SetProcessDPIAware().
+// Must be called before wxEntry().
+extern WXDLLIMPEXP_CORE void wxMSWDisableSettingHighDPIAware();
+
 // Windows-only overloads of wxEntry() and wxEntryStart() which take the
 // parameters passed to WinMain() instead of those passed to main()
 extern WXDLLIMPEXP_CORE bool