Revert "Work around nested virt issues on OVH test nodes"

The nested virt issues we saw on OVH should be resolved now.
More information here: I980cdbc67d6e7b3a8a2520b2279ff3a1cdf68c4b

This reverts commit cc98ed84f166cc7dd09ff0157764b3f4d06391b6.

Change-Id: Ia3d5ca1c3490ee9dbc50a4a7a9207157cbb9f5fd

tests/roles/bootstrap-host/tasks/prepare_aio_config.yml

@@ -66,10 +66,6 @@
   when:
     - nodepool_dir.stat.exists
   block:
-    # OVH nodepool nodes have an issue which causes nested virt
-    # instances to crash with a hardware error, then a dump.
-    # We therefore detect whether we're running on OVH and
-    # force it to use qemu instead.
     - name: Discover the OpenStack-Infra mirrors
       shell: |
         source /etc/ci/mirror_info.sh
@@ -80,9 +76,6 @@
         echo "centos_epel_mirror: '${NODEPOOL_EPEL_MIRROR}'" >> ${NODEPOOL_OVERRIDES}
         echo "galera_percona_xtrabackup_repo_host: '${NODEPOOL_PERCONA_PROXY}'" >> ${NODEPOOL_OVERRIDES}
         echo "openstack_hosts_rdo_mirror_url: '${NODEPOOL_RDO_PROXY}'" >> ${NODEPOOL_OVERRIDES}
-        if [[ ${NODEPOOL_PYPI_MIRROR} == *.ovh.* ]]; then
-          echo "nova_virt_type: 'qemu'" >> ${NODEPOOL_OVERRIDES}
-        fi
         echo "repo_build_pip_default_index: '${NODEPOOL_PYPI_MIRROR}'" >> ${NODEPOOL_OVERRIDES}
       args:
         executable: /bin/bash