rtc: rv3028: Use IRQ flags obtained from device tree if available

Make the interrupt pin of the RV3028 usable with GPIO controllers
without level type IRQs support, such as the TI Davinci GPIO controller.

Therefore, allow the IRQ type to be passed from the device tree if
available.

Based on commit d4785b46 ("rtc: pcf2127: use IRQ flags obtained from device tree if available")

Signed-off-by: Wadim Egorov <w.egorov@phytec.de>
Link: https://lore.kernel.org/r/20221208133605.4193907-1-w.egorov@phytec.de


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