rtc: tps6586x: Use IRQ_NOAUTOEN flag

The IRQ_NOAUTOEN flag tells interrupt core that interrupt shall not be
auto-enabled at the time of requesting interrupt. This is a minor clean-up
change that doesn't fix any problems.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200106015615.12602-1-digetx@gmail.com


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