The kernel API for requesting interrupts and the associated callback
have a somewhat strange behaviour. Requesting an interrupts is done
by calling sys_irqsetpolicy using an interrupt and a given id. This
id can be modified by the sys_irqsetpolicy and must be used for
subsequent calls to sys_irqenable/sys_irqdisable. However upon an
incoming call from the kernel NOTIFY_ARG contains the original value
encoded in a set e.g. if 1 << id == true the interrupt was raised.
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