Merge pull request ocaml#23369 from Leonidas-from-XIV/xml-light-build

Add `build` field to XML-Light 2.4

Author: kit-ty-kate

packages/xml-light/xml-light.2.4/opam

@@ -6,6 +6,10 @@ depends: [
   "ocamlfind"
 ]
 dev-repo: "git+https://github.com/ncannasse/xml-light"
+build: [
+  [make "all"]
+  [make "opt"]
+]
 install: [make "install_ocamlfind"]
 synopsis: "Xml-Light is a minimal XML parser & printer for OCaml"
 description: """