Update rhel7.6 to rhel7.7
Change-Id: I08a15c2a8fce08d1b05504a0a138c20190fed5b9
Signed-off-by: Junqin Zhou <juzhou@redhat.com>
Reviewed-on: https://code.engineering.redhat.com/gerrit/181198
Tested-by: Libvirt Jenkins <libvirt-jenkins@redhat.com>
Reviewed-by: Liping Cheng <lcheng@redhat.com>
Signed-off-by: Liping Cheng <lcheng@redhat.com>