Add gcc to dependency list for ppc64le containers build job
Add gcc to dependency list for ppc64le containers build job

This patch installs gcc on the remote node when building Triple O
containers on ppc64le, as the errors thrown by the cffi build
indicate there's no working C compiler on the remote system by
default.

Change-Id: I4b3d8fb8bd6ebcd452b4c91c10e5ac9825c8728c

redhat-openstack/rdo-infra,rdo-infra/ci-config,redhat-openstack/rdo-infra,redhat-openstack/rdo-infra,redhat-openstack/rdo-infra,rdo-infra/ci-config,rdo-infra/ci-config,rdo-infra/ci-config