power: supply: Fix missing IRQF_ONESHOT as only threaded handler

Coccinelle noticed:
drivers/power/supply/ab8500_btemp.c:1107:8-28: ERROR: Threaded IRQ with
no primary handler requested without IRQF_ONESHOT.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>