[media] coda: fix first encoded frame payload

During the recent vb2_buffer restructuring, the calculation of the
buffer payload reported to userspace was accidentally broken for the
first encoded frame, counting only the length of the headers.
This patch re-adds the length of the actual frame data.

Fixes: 2d7007153f0c ("[media] media: videobuf2: Restructure vb2_buffer")

Reported-by: Michael Olbrich <m.olbrich@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Jan Luebbe <jlu@pengutronix.de>
Cc: <stable@vger.kernel.org>      # for v4.4 and up
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/coda/coda-bit.c

@@ -1342,7 +1342,7 @@ static void coda_finish_encode(struct coda_ctx *ctx)
 
 	/* Calculate bytesused field */
 	if (dst_buf->sequence == 0) {
-		vb2_set_plane_payload(&dst_buf->vb2_buf, 0,
+		vb2_set_plane_payload(&dst_buf->vb2_buf, 0, wr_ptr - start_ptr +
 					ctx->vpu_header_size[0] +
 					ctx->vpu_header_size[1] +
 					ctx->vpu_header_size[2]);