rtc: pcf2127: remove useless driver version

A driver version is only really sensible for oot drivers. Also the
dev_info about having found a chip only signals that allocating the
driver data succeeded and so isn't worth much.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>