Fix leak in k5_free_cammac()

free_vmac(), a helper function used by k5_free_cammac(), must free its
val pointer as well as the contents; otherwise the krb5_verifier_mac
container is leaked.

https://github.com/krb5/krb5/commit/d9d6e7e9aa619d5bd35fa6e4468683ee7ddb5e5d
Author: Greg Hudson <ghudson@mit.edu>
Commit: d9d6e7e9aa619d5bd35fa6e4468683ee7ddb5e5d
Branch: master
 src/lib/krb5/krb/kfree.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)