Select the correct EINT configuration register when configuring
the external interrupt level/edge type.
Signed-off-by: NMatt Hsu <matt_hsu@openmoko.org>
[ben-linux@fluff.org: description improvement]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Add the necessary code to support IRQ_EINT(x) on
the S3C64XX series of CPUs.

Note, since there is no GPIO configuration support
in the kernel, the irq set_type method does not
configure the relevant pin to interrupt.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>