qisrc reset: fix crash when loading bad snapshot

Change-Id: I5dfefd3c53e8052bf6ee2e1ecd69aea0c78ddf65
Reviewed-on: http://gerrit.aldebaran.lan/49812
Reviewed-by: dmerejkowsky <dmerejkowsky@aldebaran-robotics.com>
Tested-by: dmerejkowsky <dmerejkowsky@aldebaran-robotics.com>