Proposed errata: remove reference to identity provider discovery service from ECP Profile

Delete lines 725 and 726 from saml-profiles-2.0-os, starting at "The ECP MAY use...".

 

Rationale: The ECP does not directly interact with the identity provider discovery service, it may act as an intermediary for an IdP or SP that plan to utilize the service. Current text gives the impression that it is a direct participant in the identity provider discovery service. Instead, the main issue is that it should not impede service interactions with an SP or IdP.