If an AMI user without the "system" authorization calls the
Originate AMI command with the Originate application,
the second Originate could run the "System" command.

Action: Originate
Channel: Local/1111
Application: Originate
Data: Local/2222,app,System,touch /tmp/owned

If the "system" authorization isn't set, we now block the
Originate app as well as the System, Exec, etc. apps.

ASTERISK-28580
Reported by: Eliel Sardañons

Change-Id: Ic4c9dedc34c426f03c8c14fce334a71386d8a5fa