xive/p10:: Declare xive2 DT node as an interrupt-controller
xive/p10:: Declare xive2 DT node as an interrupt-controller

This patch fixes errors seen when linux looks for the interrupt to use
for a device LSI:

     pci X:Y:Z of_irq_parse_pci: failed with rc=-22

The of/irq parsing code requires those new properties to be able to
map the interrupt specifier correctly. It was not needed before
comitting cd12ea6d8e1 ("interrupts: Do not advertise XICS support on
P10"), because the LSI mapping code was defaulting to the XICS
interrupt controller node, which is now removed (and had those
properties).

Fixes: cd12ea6d8e1 ("interrupts: Do not advertise XICS support on P10")
Signed-off-by: Frederic Barrat <c90240987c583ac0802fbeb88cb1684edc683e18@linux.ibm.com>
Reviewed-by: Cédric Le Goater <2d8cace2254d4e43578d21933db015d84bcc468a@kaod.org>
Signed-off-by: Vasant Hegde <a6d753843573f7bfed5075c1e875b0be8007a0ab@linux.vnet.ibm.com>

open-power/skiboot,shenki/skiboot,legoater/skiboot,legoater/skiboot,legoater/skiboot,qemu/skiboot,qemu/skiboot,qemu/skiboot,open-power/skiboot,qemu/skiboot,legoater/skiboot,legoater/skiboot,shenki/skiboot,open-power/skiboot,shenki/skiboot,shenki/skiboot,shenki/skiboot,qemu/skiboot,open-power/skiboot,open-power/skiboot