rtc: sh: only disable carry interrupts in probe()

With old, custom UIE handling removed, we can now disable the carry
interrupt in probe() and leave it like this. No further handling is
required.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20250227134256.9167-13-wsa+renesas@sang-engineering.com


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