P2P:initiate provisioning on persistant group removed.

The initiator, on a response from the peer with unknown group during
the persistent reinvocation has to transit to the provisioning state
to handle all the config methods (PIN and PBC).
This commit ensures the same.

Change-Id: Iafd8e14681628c002f613172ad36a1da7efb5369
CRs-fixed: 653078