zynqmp: pm: Added NODE_IPI_APU slave node ID in pm_defs.h

NODE_IPI_APU is the node ID of APU's IPI device. If APU should be
woken-up on an IPI from FPD power down, this node shall be set as
the wake-up source upon suspend.
Signed-off-by: Mirela Simonovic <mirela.simonovic@aggios.com>

plat/xilinx/zynqmp/pm_service/pm_defs.h

@@ -142,6 +142,7 @@ enum pm_node_id {
 	NODE_RPLL,
 	NODE_IOPLL,
 	NODE_DDR,
+	NODE_IPI_APU,
 };
 
 enum pm_request_ack {