Fix Makefile for OSX

Bump base SDK from 10.5 -> 10.7
Just use the builtin __APPLE__

code/client/qal.h

@@ -37,8 +37,9 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 #include "../AL/al.h"
 #include "../AL/alc.h"
 #else
-#ifdef _MSC_VER
+#if defined(_MSC_VER) || defined(__APPLE__)
   // MSVC users must install the OpenAL SDK which doesn't use the AL/*.h scheme.
+  // OSX framework also needs this
   #include <al.h>
   #include <alc.h>
 #else