spapr: Simplify error handling in prop_get_fdt()

Use the return value of visit_check_struct() and visit_check_list()
for error checking instead of local_err. This allows to get rid of
the error propagation overhead.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200914123505.612812-10-groug@kaod.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/ppc/spapr_drc.c

@@ -302,7 +302,6 @@ static void prop_get_fdt(Object *obj, Visitor *v, const char *name,
 {
     SpaprDrc *drc = SPAPR_DR_CONNECTOR(obj);
     QNull *null = NULL;
-    Error *err = NULL;
     int fdt_offset_next, fdt_offset, fdt_depth;
     void *fdt;
 
@@ -321,6 +320,7 @@ static void prop_get_fdt(Object *obj, Visitor *v, const char *name,
         const struct fdt_property *prop = NULL;
         int prop_len = 0, name_len = 0;
         uint32_t tag;
+        bool ok;
 
         tag = fdt_next_tag(fdt, fdt_offset, &fdt_offset_next);
         switch (tag) {
@@ -334,10 +334,9 @@ static void prop_get_fdt(Object *obj, Visitor *v, const char *name,
         case FDT_END_NODE:
             /* shouldn't ever see an FDT_END_NODE before FDT_BEGIN_NODE */
             g_assert(fdt_depth > 0);
-            visit_check_struct(v, &err);
+            ok = visit_check_struct(v, errp);
             visit_end_struct(v, NULL);
-            if (err) {
-                error_propagate(errp, err);
+            if (!ok) {
                 return;
             }
             fdt_depth--;
@@ -355,10 +354,9 @@ static void prop_get_fdt(Object *obj, Visitor *v, const char *name,
                     return;
                 }
             }
-            visit_check_list(v, &err);
+            ok = visit_check_list(v, errp);
             visit_end_list(v, NULL);
-            if (err) {
-                error_propagate(errp, err);
+            if (!ok) {
                 return;
             }
             break;