V4L/DVB (5558): Opera: use 7-bit i2c addresses

- the tuner i2c addr now without define (as wanted).
- now 7 bit addr are used (the power_ctrl fkt ist ok so,
  because this is a raw write)
- the addr >> 1 , addr << 1 is ok so, i think beause the
  read write is now taken from the last bit.
- now i have no datasheet for the device, all taken from usb-logs

Signed-off-by: Marco Gittler <g.marco@freenet.de>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>