tty: audit: Never audit packet mode

tty audit never logs pty master reads, but packet mode only works for
pty masters, so tty_audit_add_data() was never logging packet mode
anyway.

Don't audit packet mode data. As those are the lone call sites, remove
tty_put_user().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>