BannedFilesTest: block setuid "ip" command, fix tcpdump

Don't allow a setuid/setgid "ip" command.  The "ip" command can
modify the network routing tables, which may allow a malicious attacker
to intercept and modify network traffic to and from the device.

Add an additional check for tcpdump in /vendor/bin

Change-Id: Ied72676fd67582b30cbcafab2210346a0f9d9536
1 file changed