Remove update_extra_routes()

After Ie6ebb5f8e336e702b746ba9361fe452b390ffd8c , update_router() and
update_extra_routes() do the same operation. So this patch removes
a redundant update_extra_routes() for the code cleanup.

Change-Id: Iee748673f2d59f27de773993729999dc67f7f4d9
diff --git a/tempest/api/network/test_routers.py b/tempest/api/network/test_routers.py
index 398a0b8..75a4d6a 100644
--- a/tempest/api/network/test_routers.py
+++ b/tempest/api/network/test_routers.py
@@ -303,7 +303,7 @@
             )
 
         test_routes.sort(key=lambda x: x['destination'])
-        extra_route = self.routers_client.update_extra_routes(
+        extra_route = self.routers_client.update_router(
             router['id'], routes=test_routes)
         show_body = self.routers_client.show_router(router['id'])
         # Assert the number of routes
diff --git a/tempest/services/network/json/routers_client.py b/tempest/services/network/json/routers_client.py
index 22f5a37..c1dfda0 100644
--- a/tempest/services/network/json/routers_client.py
+++ b/tempest/services/network/json/routers_client.py
@@ -42,16 +42,6 @@
         uri = '/routers'
         return self.list_resources(uri, **filters)
 
-    def update_extra_routes(self, router_id, **kwargs):
-        """Update Extra routes.
-
-        Available params: see http://developer.openstack.org/
-                              api-ref-networking-v2-ext.html#updateExtraRoutes
-        """
-        uri = '/routers/%s' % router_id
-        put_body = {'router': kwargs}
-        return self.update_resource(uri, put_body)
-
     def delete_extra_routes(self, router_id):
         uri = '/routers/%s' % router_id
         put_body = {