libmcrypt: Fixed missing nmedit on darwin (#15775)

pkgs/development/libraries/libmcrypt/default.nix

···
-{ stdenv, fetchurl, disablePosixThreads ? false }:
+{ stdenv, fetchurl, darwin, disablePosixThreads ? false }:
 
 with stdenv.lib;
 
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     sha256 = "0gipgb939vy9m66d3k8il98rvvwczyaw2ixr8yn6icds9c3nrsz4";
   };
 
-  buildInputs = [];
+  buildInputs = optional stdenv.isDarwin darwin.cctools;
 
   configureFlags = optional disablePosixThreads
     [ "--disable-posix-threads" ];
···
     description = "Replacement for the old crypt() package and crypt(1) command, with extensions";
     homepage = http://mcrypt.sourceforge.net;
     license = "GPL";
+    platforms = platforms.all;
   };
 }