V4L/DVB (5784): Dibusb-mb: fix tuner autodetection regression

We must set i2c_msg.addr in order for the autodetection test to succeed!

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>