linux-wandboard

MLK-14978 irqchip: irqsteer: add NXP imx8 irq steer controller support

The IrqSteer module redirects/steers the incoming interrupts to output
interrupts of a selected/designated channel as specified by a set of
configuration registers.

NXP i.MX8x chips integrate IrqSteer controller for some DSC to share irq
line for all modules in the subsystem which can reduce the IRQ lines
connected to the parent interrupt controller GIC, so IrqSteer irqchip
acts as the second irq domain in the system.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>