Another fix for 4-way universal builds, use the right #ifndef guard
to detect the OSX 10.5 SDK.
diff --git a/Mac/Modules/MacOS.c b/Mac/Modules/MacOS.c
index 07a3434..272fe8d 100644
--- a/Mac/Modules/MacOS.c
+++ b/Mac/Modules/MacOS.c
@@ -30,7 +30,7 @@
 #include <Carbon/Carbon.h>
 #include <ApplicationServices/ApplicationServices.h>
 
-#ifndef HAVE_MACOS105_SDK
+#ifndef HAVE_OSX105_SDK
 typedef SInt16	FSIORefNum;
 #endif