usb-host: fix usb3ep0quirk test

usb->speed is the usb speed the device is actually running on in the
qemu emulation (i.e. from the guests point of view).  So when plugging
usb3 devices into ehci hostadapter this is HIGH not SUPER.

To figure whenever the host talks to the device with superspeed we
have to check speedmask instead and see whenever the superspeed bit
is set there.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1445603230-11840-1-git-send-email-kraxel@redhat.com
