staging: vt6656: use off stack for in buffer USB transfers.

staging: vt6656: use off stack for in buffer USB transfers.

BugLink: http://bugs.launchpad.net/bugs/1692900
commit 05c0cf88bec588a7cb34de569acd871ceef26760 upstream.

Since 4.9 mandated USB buffers to be heap allocated. This causes
the driver to fail.

Create buffer for USB transfers.

Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>