tempest fix: install pip requirements

have to specify the virtenv for the pip requirements install

Change-Id: Ib9c8ab62beec18f14a3830763111bc55231957ae
Set libvirt_type to qemu on kvm compute node

When a compute node is a kvm guest, set the libvirt_type to qemu. This
will only run if node_compute_fix is set to yes.

Change-Id: I2d8347640c55efe7d78ba9f71b7d8413f95b448e
tempest fedora: turn on mariadb workaround by default

Change-Id: Ic93688d58ce6a31890b86e977905b74fade7e45a