USB: ftdi_sio: fix DMA buffers on stack

Also remove unnecessary buffer allocations for zero-length transfers.

Reported-by: Matti Aarnio <matti.aarnio@zmailer.org>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 file changed