osinfo: Enable NIC hotplugging in ppc64

This patch enables NIC hotplugging in ppc64 guests, since it is
supported in PowerKVM.

Change-Id: I755c599c2b93ee901b51572415b95841cb5263c1
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1154630
Signed-off-by: Vitor de Lima <vdelima@redhat.com>