rtc: da9063: Mark the alarm IRQ as a wake IRQ

rtc: da9063: Mark the alarm IRQ as a wake IRQ

This keeps the IRQ enabled during system suspend, if the RTC's wakeup
source is enabled. Since the IRQ is not required to wake from shutdown,
continue to add the wakeup source even if registering the wakeirq fails.
See commit 029d3a6f2f3c ("rtc: da9063: add as wakeup source").

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20230717190937.1301509-1-samuel.holland@sifive.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>