Check if FV_K8SIMAGE and FV_TYPHAIMAGE are defined for k8s FV.
Check if FV_K8SIMAGE and FV_TYPHAIMAGE are defined for k8s FV.

The test will abort execution if typha or hyperkube images
are not defined in the environment.

Signed-off-by: David Wilder <c99dc2f4f8d2e2b13883c936de59f520004971aa@us.ibm.com>

neiljerram/felix,neiljerram/felix,Metaswitch/calico,neiljerram/felix,neiljerram/felix,Metaswitch/calico