Input: synaptics-rmi4 - fix video buffer size

The video buffer used by the queue is a vb2_v4l2_buffer, not a plain
vb2_buffer. Using the wrong type causes the allocation of the buffer
storage to be too small, causing a out of bounds write when
__init_vb2_v4l2_buffer initializes the buffer.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Fixes: 3a762dbd ("[media] Input: synaptics-rmi4 - add support for F54 diagnostics")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191104114454.10500-1-l.stach@pengutronix.deSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/rmi4/rmi_f54.c

@@ -359,7 +359,7 @@ static const struct vb2_ops rmi_f54_queue_ops = {
 static const struct vb2_queue rmi_f54_queue = {
 	.type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
 	.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF | VB2_READ,
-	.buf_struct_size = sizeof(struct vb2_buffer),
+	.buf_struct_size = sizeof(struct vb2_v4l2_buffer),
 	.ops = &rmi_f54_queue_ops,
 	.mem_ops = &vb2_vmalloc_memops,
 	.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC,