V4L/DVB (7429): tda18271: write EP3 thru MD3 for image rejection low band initialization

Both the tda18271 c1 and c2 parts only need EP3 through MD3 to be written for
the image rejection calibration's low band initialization.

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