ARM: dts: aspeed: bletchley: Add interrupt support for sled io expander

Enable interrupt support for all sledx_ioexp, so userspace can monitor
gpio from io expander by interrupt.

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Patrick Williams <patrick@stwcx.xyz>
Link: https://lore.kernel.org/r/20220215163151.32252-7-potin.lai@quantatw.com


Signed-off-by: Joel Stanley <joel@jms.id.au>