Remove the private option from include_role

The private option on include role was never implemented and
will no longer be developed. This change removes the option
so ansible no longer raises a deprecation warning.

Change-Id: I419cdf1a38f6fc8431934b3fe112ffaf8776aaac
Signed-off-by: Kevin Carter <kevin.carter@rackspace.com>

tasks/gnocchi_install.yml

@@ -37,7 +37,6 @@
 - name: Install the python venv
   include_role:
     name: "python_venv_build"
-    private: yes
   vars:
     venv_install_destination_path: "{{ gnocchi_bin | dirname }}"
     venv_install_distro_package_list: "{{ gnocchi_distro_packages }}"

tasks/main.yml

@@ -41,7 +41,6 @@
 - name: Run the systemd service role
   include_role:
     name: systemd_service
-    private: true
   vars:
     systemd_user_name: "{{ gnocchi_system_user_name }}"
     systemd_group_name: "{{ gnocchi_system_group_name }}"