log, journal view: fix access to `me` after destroying

log, journal view: fix access to `me` after destroying

it can happen that the view is destroyed during an api call, so we
should check if it's destroyed as the first thing in the callback

if the view is destroyed, there is nothing we can do here, so simply
return

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>