Merge pull request ocaml#22738 from samoht/irmin

Old versions of irmin needs an old version of cstruct

Author: kit-ty-kate

packages/irmin/irmin.1.3.2/opam

@@ -18,7 +18,7 @@ depends: [
   "result"  {< "1.5"}
   "fmt" {>= "0.8.0"}
   "uri" {>= "1.3.12"}
-  "cstruct" {>= "1.6.0"}
+  "cstruct" {>= "1.6.0" & < "6.1"}
   "jsonm" {>= "1.0.0"}
   "lwt" {>= "2.4.7"}
   "ocamlgraph"

packages/irmin/irmin.1.4.0/opam

@@ -18,7 +18,7 @@ depends: [
   "result" {< "1.5"}
   "fmt" {>= "0.8.0"}
   "uri" {>= "1.3.12"}
-  "cstruct" {>= "1.6.0"}
+  "cstruct" {>= "1.6.0" & < "6.1"}
   "jsonm" {>= "1.0.0"}
   "lwt" {>= "2.4.7"}
   "ocamlgraph"