basertpsession: Check if connection is NULL before storing it
basertpsession: Check if connection is NULL before storing it

Change-Id: Idff946f2138f1dddada5fc184f15dda9328436f3

ESTOS/kms-core,Kurento/kms-core,Kurento/kms-core,Kurento/kms-core,ESTOS/kms-core,Kurento/kms-core,ESTOS/kms-core,ESTOS/kms-core