[PATCH 5/6] ARCv2: IRQ: Use build registers for getting numbers of interrupts

This enhancement allows to mask all available common interrupts in IDU interrupt controller in boot time since the kernel can discover a number of them from the build register. Also now there is no need to specify in device tree a list of used core interrupts by IDU. E.g. before: idu_intc:

[PATCH 5/6] ARCv2: IRQ: Use build registers for getting numbers of interrupts

This enhancement allows to mask all available common interrupts in IDU interrupt controller in boot time since the kernel can discover a number of them from the build register. Also now there is no need to specify in device tree a list of used core interrupts by IDU. E.g. before: idu_intc: