Update Lightrec 2023-02-08 (#715)

Update Lightrec 2023-02-08 (#715)

* git subrepo pull --force deps/lightrec

subrepo:
  subdir:   "deps/lightrec"
  merged:   "3ff589bcb7"
upstream:
  origin:   "https://github.com/pcercuei/lightrec.git"
  branch:   "master"
  commit:   "3ff589bcb7"
git-subrepo:
  version:  "0.4.3"
  origin:   "https://github.com/ingydotnet/git-subrepo.git"
  commit:   "2f68596"

* lightrec: Add new C files to the Makefile

Lightrec v0.7 added a "constprop.c" source file which we need to compile
as well.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---------

Signed-off-by: Paul Cercueil <paul@crapouillou.net>