libempathy: Remove empathy_create_individual_from_tp_contact()

It has been replaced by empathy_ensure_individual_from_tp_contact(),
which can’t cause internal state corruption in libfolks by wrapping an
existing Persona in a second Individual when it’s already wrapped in
one.

This has also been fixed in libfolks.

See: https://bugzilla.redhat.com/show_bug.cgi?id=1031252

https://bugzilla.gnome.org/show_bug.cgi?id=712839