Use MAP_ANON if MAP_ANONYMOUS is not defined.

MAP_ANON has been deprecated in favor of MAP_ANONYMOUS, but Mac OS only
defines MAP_ANON.

Bug chromium:630728

Change-Id: I7345a5f9227acbc0caa29d8103855ab531f16499
Reviewed-on: https://swiftshader-review.googlesource.com/8531
Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Nicolas Capens <capn@google.com>
diff --git a/src/Reactor/SubzeroReactor.cpp b/src/Reactor/SubzeroReactor.cpp
index 2a5bad0..21298f8 100644
--- a/src/Reactor/SubzeroReactor.cpp
+++ b/src/Reactor/SubzeroReactor.cpp
@@ -40,6 +40,9 @@
 #include <Windows.h>
 #else
 #include <sys/mman.h>
+#if !defined(MAP_ANONYMOUS)

+#define MAP_ANONYMOUS MAP_ANON

+#endif
 #endif
 
 #include <mutex>