regmap-irq: set IRQF_ONESHOT flag to ensure IRQ request

Since commit 1c6c6952 ("genirq: Reject
bogus threaded irq requests") threaded IRQs without a primary handler
need to be requested with IRQF_ONESHOT, otherwise the request will fail.

The %irq_flags flag is used to request the threaded IRQ and is also a
parameter of the caller.  Hence, we cannot be sure that IRQF_ONESHOT is
set.  This change avoids the potentially missing flag by setting
IRQF_ONESHOT when requesting the threaded IRQ.

Generated by: scripts/coccinelle/misc/irqf_oneshot.cocci

Signed-off-by: Valentin Rothberg <Valentin.Rothberg@lip6.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>