V4L/DVB (7071): DiB0700: Start streaming the right way

There was a mistake in the way how to start the streaming in the dib0700. This patch fixes that.

Signed-off-by: Patrick Boettcher <pb@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>