pcf85063_get_datetime() tries to handle a century bit but that bit is not
documented and the final value is never used anywhere else in the kernel.
Reviewed-by: NJuergen Borleis <jbe@pengutronix.de>
Tested-by: NUlrich Ölmann <u.oelmann@pengutronix.de>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>