MIPS: DEC: Remove IRQF_ONESHOT reference for IOASIC DMA error IRQs

MIPS: DEC: Remove IRQF_ONESHOT reference for IOASIC DMA error IRQs

There is no need for IOASIC DMA error interrupts to use the IRQF_ONESHOT
flag, because while they do need to have the source cleared only at the
conclusion of handling, the action handler supplied is either run in the
hardirq context with interrupts disabled at the CPU level or, where IRQ
threading has been forced, the primary handler has the IRQF_ONESHOT flag
implicitly added and therefore the original action handler, now run as
the thread handler and with interrupts enabled in the CPU, is executed
with the originating interrupt line masked.  Therefore no interrupt will
retrigger regardless until the original request has been handled.

Link: https://lore.kernel.org/r/20260127135334.qUEaYP9G@linutronix.de/
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>