ceph-common: remove ganesha old ppa

The ppa does not exist anymore and makes any installation with
stable-2.1 fail.

Closes: https://github.com/ceph/ceph-ansible/issues/2286
Signed-off-by: Sébastien Han <seb@redhat.com>

roles/ceph-common/tasks/installs/debian_ceph_repository.yml

@@ -51,15 +51,3 @@
     state: present
   changed_when: false
   when: ceph_custom
-
-- name: add gluster nfs ganesha repo
-  apt_repository:
-    repo: "{{ item }}"
-    state: present
-  with_items:
-    - ppa:gluster/libntirpc
-    - ppa:gluster/nfs-ganesha
-  changed_when: false
-  when:
-    - (nfs_obj_gw or nfs_file_gw)
-    - not ansible_distribution == "Debian"