feat(3p/lisp/sclf): build using buildLisp

Adding the default.nix is quite straightforward, however we have to make
today's SBCL happy: due to package locking it no longer likes sclf using
an sb-impl internal constant for some reason. This is however a good
opportunity to clean up the stat-*-time code: It converted the times in
an implementation specific way even though time.lisp does provide a
generic way to convert between unix and universal time. Note that the
updated ASDF file is untested, but should be a trivial enough change.

Change-Id: If193bf830ac704cc53e0855d8e9fff2b5a5ef291
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3268
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>

third_party/lisp/sclf/default.nix

@@ -0,0 +1,28 @@
+# Copyright (C) 2021 by the TVL Authors
+# SPDX-License-Identifier: LGPL-2.1-or-later
+{ depot, pkgs, ... }:
+
+depot.nix.buildLisp.library {
+  name = "sclf";
+
+  deps = [
+    (depot.nix.buildLisp.bundled "sb-posix")
+  ];
+
+  srcs = [
+    ./package.lisp
+    ./sclf.lisp
+    ./sysproc.lisp
+    ./lazy.lisp
+    ./time.lisp
+    ./directory.lisp
+    ./serial.lisp
+    ./mp/sbcl.lisp
+  ];
+
+  # TODO(sterni): implement OS interaction for ECL and CCL
+  brokenOn = [
+    "ecl"
+    "ccl"
+  ];
+}