powerpc/powernv/pci: Check status of a PHB before using it

If the firmware encounters an error (internal or HW) during initialization
of a PHB, it might leave the device-node in the tree but mark it disabled
using the "status" property. We should check it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/powernv/pci-ioda.c

@@ -3516,6 +3516,9 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
 	void *aux;
 	long rc;
 
+	if (!of_device_is_available(np))
+		return;
+
 	pr_info("Initializing %s PHB (%s)\n",
 		pnv_phb_names[ioda_type], of_node_full_name(np));