pnv/phb4: Fix error path in pnv_pec_realize()

Obviously, we want to pass &local_err so that we can check it then
line below, not errp.

Reported-by: Coverity CID 1419395 'Constant' variable guards dead code
Fixes: 4f9924c4 "ppc/pnv: Add models for POWER9 PHB4 PCIe Host bridge"
Signed-off-by: NGreg Kurz <groug@kaod.org>
Message-Id: <158153364605.3229002.2796177658957390343.stgit@bahia.lan>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

hw/pci-host/pnv_phb4_pec.c

@@ -391,7 +391,7 @@ static void pnv_pec_realize(DeviceState *dev, Error **errp)
 
         object_property_set_int(stk_obj, i, "stack-no", &error_abort);
         object_property_set_link(stk_obj, OBJECT(pec), "pec", &error_abort);
-        object_property_set_bool(stk_obj, true, "realized", errp);
+        object_property_set_bool(stk_obj, true, "realized", &local_err);
         if (local_err) {
             error_propagate(errp, local_err);
             return;