fixed correct ansible variable name

Change-Id: Ie97c4253dc7c5df244b83a22445a645a8d6e675e
diff --git a/playbooks/roles/lab-debian-backports/tasks/main.yml b/playbooks/roles/lab-debian-backports/tasks/main.yml
index 618a352..d73da45 100644
--- a/playbooks/roles/lab-debian-backports/tasks/main.yml
+++ b/playbooks/roles/lab-debian-backports/tasks/main.yml
@@ -10,7 +10,7 @@
 
  - name: Adding buster backports
    copy: src=backports-buster.list dest=/etc/apt/sources.list.d/backports.list owner=root group=root mode=644
-   when: codename == "buster"
+   when: ansible_lsb.codename == "buster"
 
  - name: Update apt
    apt: update_cache=yes
diff --git a/playbooks/roles/lab-snmp/tasks/main.yml b/playbooks/roles/lab-snmp/tasks/main.yml
index 71d119c..e66a001 100644
--- a/playbooks/roles/lab-snmp/tasks/main.yml
+++ b/playbooks/roles/lab-snmp/tasks/main.yml
@@ -18,11 +18,11 @@
 
  - name: Adding contrib buster
    copy: src=contrib-buster.list dest=/etc/apt/sources.list.d/contrib.list owner=root group=root mode=644
-   when: codename == "buster"
+   when: ansible_lsb.codename == "buster"
 
  - name: Adding non-free buster
    copy: src=nonfree-buster.list dest=/etc/apt/sources.list.d/nonfree.list owner=root group=root mode=644
-   when: codename == "buster"
+   when: ansible_lsb.codename == "buster"
 
  - name: Update apt
    apt: update_cache=yes