DDSSEC12 — validate_remote_permissions interaction with Authentication Plugin

Table 63's entry for validate_remote_permissions describes a required interaction with the authentication plugin in order to obtain an AuthenticatedPeerCredentialToken. This appears to be an artifact of a previous spec revision, since the current API for validate_remote_permissions already provides the AuthenticatedPeerCredentialToken.

So that validate_remote_permissions makes more sense, remove the auth_plugin and remote_identity_handle parameters (Table 32, section 8.4.2.9.2, Table 63, IDL).