nixos/manual: fix inclusion of FoundationDB documentation

Signed-off-by: Austin Seipp <[e-mail]>

nixos/modules/services/databases/foundationdb.nix

···
   };
 
   config = mkIf cfg.enable {
-    meta.doc         = ./foundationdb.xml;
-    meta.maintainers = with lib.maintainers; [ thoughtpolice ];
-
     environment.systemPackages = [ pkg ];
 
     users.users = optionalAttrs (cfg.user == "foundationdb") (singleton
···
       '';
     };
   };
+
+  meta.doc         = ./foundationdb.xml;
+  meta.maintainers = with lib.maintainers; [ thoughtpolice ];
 }

nixos/modules/services/databases/foundationdb.xml

···
          xmlns:xlink="http://www.w3.org/1999/xlink"
          xmlns:xi="http://www.w3.org/2001/XInclude"
          version="5.0"
-         xml:id="module-foundationdb">
+         xml:id="module-services-foundationdb">
 
 <title>FoundationDB</title>