pci-slot: Allow to create slot for downstream port of any switch

System vendor may build systems with large PCIe tree with
deeper switch topologies. Currenlty downstream ports slot
creation is limited to first switch. Patch allows to use any.

Signed-off-by: Ilya Kuznetsov <ilya@yadro.com>
[oliver: added pci-slot prefix]
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>

core/pcie-slot.c

@@ -544,13 +544,8 @@ struct pci_slot *pcie_slot_create_dynamic(struct phb *phb,
 	if (!phb || !pd || pd->slot)
 		return NULL;
 
-	/* Try to create slot whose details aren't provided by platform.
-	 * We only care the downstream ports of PCIe switch that connects
-	 * to root port.
-	 */
-	if (pd->dev_type != PCIE_TYPE_SWITCH_DNPORT ||
-	    !pd->parent || !pd->parent->parent ||
-	    pd->parent->parent->parent)
+	/* Try to create slot whose details aren't provided by platform. */
+	if (pd->dev_type != PCIE_TYPE_SWITCH_DNPORT)
 		return NULL;
 
 	ecap = pci_cap(pd, PCI_CFG_CAP_ID_EXP, false);