UPSTREAM: USB: cypress_m8: add endpoint sanity check

commit c55aee1bf0e6b6feec8b2927b43f7a09a6d5f754 upstream.

An attack using missing endpoints exists.

CVE-2016-3137

BUG: 28242610
Signed-off-by: Oliver Neukum <ONeukum@suse.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Badhri Jagan Sridharan <Badhri@google.com>
Change-Id: I1cc7957a5924175d24f12fdc41162ece67c907e5