update pkg-config system package name for rhel and centos 8 and above

[bikallem]

Fixes #16332

[bikallem]

This should now allow those on ocaml 4.09 and above to be able to install graphics package correctly.

[camelus]

Commit: 064b97b

@bikallem has posted 3 contributions.

🌩️ opam-lint errors 064b97b

• conf-pkg-config.1.2 has errors:

  • error 46: Package is flagged "conf" but has source, install or remove instructions

---

☀️ Installability check (+1)

• new installable packages (1): conf-pkg-config.1.2

[kit-ty-kate]

For our own record, here is the difference between conf-pkg-config.1.1 and conf-pkg-config.1.2:

--- opam.1.1	2020-04-03 15:22:16.796495179 +0100
+++ opam.1.2	2020-05-02 13:03:29.079536186 +0100
@@ -20,15 +20,17 @@
   ["pkg-config"] {os-family = "debian"}
   ["pkg-config"] {os-distribution = "arch"}
   ["pkgconfig"] {os-distribution = "fedora"}
-  ["pkgconfig"] {os-distribution = "centos"}
+  ["pkgconfig"] {os-distribution = "centos" & os-version <= "7"}
   ["pkgconfig"] {os-distribution = "mageia"}
-  ["pkgconfig"] {os-distribution = "rhel"}
+  ["pkgconfig"] {os-distribution = "rhel" & os-version <= "7"}
   ["pkgconfig"] {os-distribution = "ol"}
   ["pkgconfig"] {os-distribution = "alpine"}
   ["pkgconfig"] {os-distribution = "nixos"}
   ["devel/pkgconf"] {os = "openbsd"}
   ["pkg-config"] {os = "macos" & os-distribution = "homebrew"}
   ["pkgconf"] {os = "freebsd"}
+  ["pkgconf-pkg-config"] {os-distribution = "rhel" & os-version >= "8"}
+  ["pkgconf-pkg-config"] {os-distribution = "centos" & os-version >= "8"}
   ["pkg-config"] {os-distribution = "cygwinports"}
 ]
 synopsis: "Virtual package relying on pkg-config installation"

Thanks!