Fix Leash AddDisplayItem() declaration

Commit a9cbbf0899f270fbb14f63ffbed1b6d542333641 changed three
parameters in AddDisplayItem() from long to time_t, but did not change
the corresponding declaration in LeashView.h.  Fix that now.

https://github.com/krb5/krb5/commit/b1367abb2e2ff14446371155cb7e23a29b76aa87
Author: Greg Hudson <ghudson@mit.edu>
Commit: b1367abb2e2ff14446371155cb7e23a29b76aa87
Branch: master
 src/windows/leash/LeashView.h |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)