fix a crash (at this point "ue_context_p" is NULL,

so "ue_context_p->ue_context.random_ue_identity"
should not be accessed, changed by "random_value")


git-svn-id: http://svn.eurecom.fr/openair4G/trunk@7388 818b1a75-f10b-46b9-bf7c-635c3b92a50f