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>