Convert OS specific packages to new format

Uses the logic introduced in the previous patch to convert all
kubernetes/preinstall/vars/* os specific files to the `pkgs`
dictionary.

Some niceties for devs:
- always validate the `pkgs` variable to catch mistakes in CI.
- ensure that `pkgs` is always sorted. This makes it easier to find the
  packages you're looking for.

roles/kubernetes/preinstall/vars/main.yml

@@ -0,0 +1,88 @@
+---
+pkgs:
+  apparmor: &debian_family_base
+    os:
+      families:
+      - Debian
+  apt-transport-https: *debian_family_base
+  aufs-tools: &deb_10
+    groups:
+    - k8s_cluster
+    os:
+      distributions:
+        Debian:
+          major_versions:
+          - "10"
+  conntrack: &deb_redhat
+    groups:
+    - k8s_cluster
+    os:
+      families:
+      - Debian
+      - RedHat
+  conntrack-tools:
+    groups:
+    - k8s_cluster
+    os:
+      families:
+      - Suse
+      distributions:
+        Amazon: {}
+  container-selinux: &redhat_family
+    groups:
+    - k8s_cluster
+    os:
+      families:
+      - RedHat
+  device-mapper:
+    groups:
+    - k8s_cluster
+    os:
+      families:
+      - Suse
+  device-mapper-libs: *redhat_family
+  gnupg: &debian
+    groups:
+    - k8s_cluster
+    os:
+      distributions:
+        Debian:
+          major_versions:
+          - "11"
+          - "12"
+  iptables: *deb_redhat
+  libseccomp: *redhat_family
+  libseccomp2:
+    groups:
+    - k8s_cluster
+    os:
+      families:
+      - Suse
+      - Debian
+  libselinux-python:  # TODO: Handle rehat_family + major < 8
+    os:
+      distributions:
+        Amazon: {}
+  libselinux-python3:
+    os:
+      distributions:
+        Fedora: {}
+  mergerfs:
+    os:
+      distributions:
+        Debian:
+          major_versions:
+          - "12"
+  nss: *redhat_family
+  python-apt: *deb_10
+  # TODO: not for debian 10
+  python3-apt: *debian_family_base
+  python3-libselinux:
+    os:
+      distributions:
+        RedHat: &major_redhat_like
+          major_versions:
+          - "8"
+          - "9"
+        Centos: *major_redhat_like
+  software-properties-common: *debian_family_base