don't redeclare wxYield() if it had been already declared to fix g++ warnings with -Wredundant-decls

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@51592 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/utils.h

@@ -733,9 +733,16 @@ inline struct _XDisplay *wxGetX11Display()
 // wxYield(): these functions are obsolete, please use wxApp methods instead!
 // ----------------------------------------------------------------------------
 
+// avoid redeclaring this function here if it had been already declated by
+// wx/app.h, this results in warnings from g++ with -Wredundant-decls
+#ifndef wx_YIELD_DECLARED
+#define wx_YIELD_DECLARED
+
 // Yield to other apps/messages
 WXDLLIMPEXP_BASE bool wxYield();
 
+#endif // wx_YIELD_DECLARED
+
 // Like wxYield, but fails silently if the yield is recursive.
 WXDLLIMPEXP_BASE bool wxYieldIfNeeded();