VNF in PENDING_SCALE_* status can't be deleted.
VNF in PENDING_SCALE_* status can't be deleted.

when VNF scale process is interrupted by some reasons,
it stays in PENDING_SCALE_IN or PENDING_SCALE_OUT status,
we cannot find it from db with _ACTIVE_UPDATE_ERROR_DEAD status.

Close-Bug: #1777568
Change-Id: I0a97c10b4392c288da8ca2e8509f6d568d8df835

openstack/tacker,openstack/tacker,openstack/tacker,stackforge/tacker,stackforge/tacker