added xorg packages for ubuntu desktop

Former-commit-id: abef5486

roles/gpu/tasks/main.yml

@@ -25,12 +25,14 @@
     - xorg-x11-xauth
     - xorg-x11-proto-devel
     - xorg-x11-xkb-utils
+  when: ansible_os_family == 'RedHat'
 
 - name: install development tools
   yum: name="@Development Tools" state=installed
   become: true
   become_user: root
   ignore_errors: yes
+  when: ansible_os_family == 'RedHat'
 
 - name: disable nouveau
   template: src=blacklist-nouveau.conf.j2 dest=/etc/modprobe.d/blacklist-nouveau.conf
@@ -99,7 +101,6 @@
   become: true
   when: install_driver
 
-
 - name: stop the persistence daemon
   service: name=nvidia-persistenced state=stopped
   become: true