Add version attribute where maintainers |= nckx

This will probably be mandatory soon, and is a step in the right
direction. Removes the deprecated meta.version, and move some meta
sections to the end of the file where I should have put them in
the first place.

pkgs/tools/filesystems/exfat/default.nix

@@ -1,8 +1,8 @@
 { stdenv, fetchFromGitHub, autoreconfHook, pkgconfig, fuse }:
 
-let version = "1.2.3"; in
 stdenv.mkDerivation rec {
   name = "exfat-${version}";
+  version = "1.2.3";
 
   src = fetchFromGitHub {
     sha256 = "147s11sqmn5flbvz2hwpl6kdfqi2gnm1c2nsn5fxygyw7qyhpzda";
@@ -15,7 +15,6 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ autoreconfHook pkgconfig ];
 
   meta = with stdenv.lib; {
-    inherit version;
     inherit (src.meta) homepage;
     description = "Free exFAT file system implementation";
     platforms = platforms.linux;