revert an unnecessary modification

CryptoLib/src/Include/CryptoLib.inc

@@ -49,7 +49,6 @@
    {$DEFINE CRYPTOLIB_UNIX}
    {$IF DEFINED(BSD)}
       {$IF DEFINED(DARWIN)}
-         {$UNDEF CRYPTOLIB_UNIX}
          {$DEFINE CRYPTOLIB_APPLE}
          {$IF DEFINED(CRYPTOLIB_ARM) OR DEFINED(CRYPTOLIB_AARCH64)}
             {$DEFINE CRYPTOLIB_IOS}
@@ -57,7 +56,6 @@
             {$DEFINE CRYPTOLIB_MACOS}
          {$IFEND}
       {$ELSEIF DEFINED(FREEBSD) OR DEFINED(NETBSD) OR DEFINED(OPENBSD) OR DEFINED(DRAGONFLY)}
-         {$UNDEF CRYPTOLIB_UNIX}
          {$DEFINE CRYPTOLIB_GENERIC_BSD}
       {$IFEND}
   {$ELSEIF DEFINED(LINUX)}