Rewrite ‘with pkgs.lib’ -> ‘with lib’

Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.

nixos/modules/services/databases/firebird.nix

@@ -1,4 +1,4 @@
-{ config, pkgs, ... }:
+{ config, lib, pkgs, ... }:
 
 # TODO: This may file may need additional review, eg which configuartions to
 # expose to the user.
@@ -19,7 +19,7 @@
 # Eg superserver is said to be most efficiently using resources according to
 # http://www.firebirdsql.org/manual/qsg25-classic-or-super.html
 
-with pkgs.lib;
+with lib;
 
 let