rtc: ds1347: set range

The DS1347 handle dates from year 0000 to 9999. Leap years are claimed to
be handled correctly in the datasheet.

Link: https://lore.kernel.org/r/20191007134724.15505-7-alexandre.belloni@bootlin.com


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>