drivers: interrupt_controller: initial support for NXP S32Z27 EIRQ

Add initial support for the NXP S32Z27 SIUL2 External
Interrupt Controller. Each SIUL2 node has a child node
will act as an interrupt-controller that processes external
interrupt signals.

This driver is required to manage GPIO interrupts.

Signed-off-by: Dat Nguyen Duy <dat.nguyenduy@nxp.com>