Fixed the build issue by removing && and moving into ifdef and ifndef statements

diff --git a/util/include/platforms/unix/axutil_unix.h b/util/include/platforms/unix/axutil_unix.h
index 1829e06..a0b00dc 100644
--- a/util/include/platforms/unix/axutil_unix.h
+++ b/util/include/platforms/unix/axutil_unix.h
@@ -121,9 +121,11 @@
 #include "axutil_date_time_util_unix.h"
 
     /* for file access handling */
-#ifdef HAVE_UNISTD_H && !defined __APPLE__
+#ifdef HAVE_UNISTD_H 
+#ifndef __APPLE__
 #include <unistd.h>
-#endif /*HAVE_UNISTD_H && !defined __APPLE__*/
+#endif /* ifndef __APPLE__ */
+#endif /* HAVE_UNISTD_H */
 
     /* network handling */
 #include <sys/socket.h>