Revert "Add note about building on Mac OS."

This has already been fixed upstream.

Author: DrLex0

README.md

@@ -57,12 +57,6 @@ make
 sudo make install
 ```
 
-On more recent Mac OS versions you may need to add an argument to configure, because of reasons:
-```
-../configure CFLAGS='-D_DARWIN_C_SOURCE' CPPFLAGS='-D_DARWIN_C_SOURCE'
-```
-
-
 # Copyright
 
 Copyright (c) 2013 WHPThomas, All rights reserved.