Prevent crash for call notification due to empty person name, using all...

Prevent crash for call notification due to empty person name, using all identification fields from vCard (first & last names, organization, job title)

https://console.firebase.google.com/u/0/project/linphone-b3ec9/crashlytics/app/android:org.linphone/issues/e5b5879e9c55605003cacecd641783e8?time=last-twenty-four-hours&versions=6.0.8%20(600008)&sessionEventKey=683D505D037E0001065A8B3F8B97FDC3_2089694057306517181