linux-phytec-ti

rtc: ds1307: remove member irq from struct ds1307

The irq number is used in the probe function only, so we don't have
to store it in struct ds1307.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>