OpenPOWER: Fix for host dump delete

If the dump is not created by host or the request is not
complete the dump id provided by the host will not be
valid. When deleting such dump entries a request for
delete should not be send to the host.

Tests:

Deleting a dump which is not finished when host is running

Signed-off-by: Dhruvaraj Subhashchandran <dhruvaraj@in.ibm.com>
Change-Id: If7e8b7fad67c215f057152bb64b5232f198fee9e