BUG 339: corrected instance-identifier translation

XML output with instance-identifier for leaf list

Change-Id: I36feadfb55dc20c802669443b45d0cea416db3a6
Signed-off-by: Jozef Gloncak <jgloncak@cisco.com>
(cherry picked from commit 9d18c1784feaab314d0fe834b78a53b8768c6019)
Merge "BUG 339: corrected instance-identifier translation" into stable/hydrogen