Fix minor memory leaks in kvno

In do_k5_kvno(), free allocated values on success as well as failure.
In t_kdb.py, run kvno with multiple arguments to manifest this leak in
asan and valgrind.  Reported by Cel Skeggs.

https://github.com/krb5/krb5/commit/16d3eaf055a2e487ca28fa71e1e57802bc47310d
Author: Greg Hudson <ghudson@mit.edu>
Commit: 16d3eaf055a2e487ca28fa71e1e57802bc47310d
Branch: master
 src/clients/kvno/kvno.c |    8 +++++---
 src/tests/t_kdb.py      |    3 +--
 2 files changed, 6 insertions(+), 5 deletions(-)