spapr: Abort on delete failure in spapr_drc_release()

We currently ignore errors from the object_property_del() in
spapr_drc_release().  But the only way that could fail is if the property
doesn't exist, in which case it's a bug that we're in spapr_drc_release()
at all.  So change from ignoring to abort()ing on errors.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

hw/ppc/spapr_drc.c

@@ -367,7 +367,7 @@ static void spapr_drc_release(sPAPRDRConnector *drc)
     g_free(drc->fdt);
     drc->fdt = NULL;
     drc->fdt_start_offset = 0;
-    object_property_del(OBJECT(drc), "device", NULL);
+    object_property_del(OBJECT(drc), "device", &error_abort);
     drc->dev = NULL;
 }