i2c: exynos5: Remove IRQF_ONESHOT

The drivers sets IRQF_ONESHOT and passes only a primary handler. The IRQ
is masked while the primary is handler is invoked independently of
IRQF_ONESHOT.
With IRQF_ONESHOT the core code will not force-thread the interrupt and
this is probably not intended. I *assume* that the original author copied
the IRQ registration from another driver which passed a primary and
secondary handler and removed the secondary handler but keeping the
ONESHOT flag.

Remove IRQF_ONESHOT.

Reported-by: Benjamin Rouxel <benjamin.rouxel@uva.nl>
Tested-by: Benjamin Rouxel <benjamin.rouxel@uva.nl>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>