Enable IO wakeup feature. This enables am437x pads to generate daisy
chained wake ups(eventually generates aprcm Interrupt) especially
when in low power modes.
Signed-off-by: Keerthy <j-keerthy@ti.com> Reviewed-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Paul Walmsley <paul@pwsan.com>