res_pjsip_endpoint_identifier_ip.c: Allow multiple IdentifyDetail AMI events.

The AMI PJSIPShowEndpoint action could only list one IdentifyDetail AMI
event per endpoint.  However, there is no reason that multiple
type=identify sections cannot identify the same endpoint.

* Reworked format_ami_endpoint_identify() to generate as many
IdentifyDetail AMI events as there are matching identifiers.

Change-Id: Ie146792aef72d78e05416ab5b27bc552a30399db