Update opam

Author: anmonteiro

packages/melange/melange.1.0.0/opam

@@ -20,6 +20,9 @@ depends: [
   "odoc" {with-doc}
 ]
 available: arch != "x86_32" & arch != "arm32"
+conflicts: [
+  "ocaml-option-bytecode-only"
+]
 build: [
   ["dune" "subst"] {dev}
   [