aerospike: Disables build on aarch64

The issue with its inclusion in the manual has been side-stepped by
matching on the platforms in supports.

nixos/modules/services/databases/aerospike.nix

···
 
       package = mkOption {
         default = pkgs.aerospike;
+        defaultText = "pkgs.aerospike";
         type = types.package;
         description = "Which Aerospike derivation to use";
       };

pkgs/servers/nosql/aerospike/default.nix

···
     description = "Flash-optimized, in-memory, NoSQL database";
     homepage = http://aerospike.com/;
     license = licenses.agpl3;
-    #platforms = [ "x86_64-linux" ];  # breaks eval of nixos manual for aarch64
-    platforms = platforms.linux;
+    platforms = [ "x86_64-linux" ];
     maintainers = with maintainers; [ kalbasit ];
   };
 }