OPAL_SET_XIVE
-------------

#define OPAL_SET_XIVE				19

WARNING: following documentation is from old sources, and is possibly
not representative of OPALv3 as implemented by skiboot. This should be
used as a starting point for full documentation.

The host calls this function to set the POWER XIVE server and priority
parameters into the PHB XIVE.

    The phb_id parameter is the value from the PHB node ibm,opal-phbid
    property.

    The xive_number is the index of an XIVE that corresponds to a particular
    interrupt

    the service_number is the server (processor) that is to receive the
    interrupt request

    the priority is the interrupt priority value applied to the interrupt
    (0=highest, 0xFF = lowest/disabled).