[ARM] 5411/1: S3C64XX: Fix EINT unmask

Currently the unmask function for EINT interrupts was setting the mask
bit rather than clearing it.  This was also previously reported and
fixed by Kyungmin Park <kyungmin.park@samsung.com> and others.
Acked-By: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/plat-s3c64xx/irq-eint.c

@@ -55,7 +55,7 @@ static void s3c_irq_eint_unmask(unsigned int irq)
 	u32 mask;
 
 	mask = __raw_readl(S3C64XX_EINT0MASK);
-	mask |= eint_irq_to_bit(irq);
+	mask &= ~eint_irq_to_bit(irq);
 	__raw_writel(mask, S3C64XX_EINT0MASK);
 }