Actually make volume extend tests validate

This fixes the previous patch to *actually* wait for the server to
be SSHABLE before continuing the test. Because the volumes tests don't
have full networking and we didn't provide validation resources to
create_server() we weren't *actually* doing the wait for ssh.

Change-Id: I783bbed4bea6137de3afa9a7ecd1a9cd37bb17e8
diff --git a/tempest/api/volume/base.py b/tempest/api/volume/base.py
index 9ba9949..ae1dc8a 100644
--- a/tempest/api/volume/base.py
+++ b/tempest/api/volume/base.py
@@ -51,6 +51,8 @@
     def setup_credentials(cls):
         cls.set_network_resources(
             network=cls.create_default_network,
+            router=cls.create_default_network,
+            dhcp=cls.create_default_network,
             subnet=cls.create_default_network)
         super(BaseVolumeTest, cls).setup_credentials()
 
diff --git a/tempest/api/volume/test_volumes_extend.py b/tempest/api/volume/test_volumes_extend.py
index 9066979..51405b8 100644
--- a/tempest/api/volume/test_volumes_extend.py
+++ b/tempest/api/volume/test_volumes_extend.py
@@ -114,7 +114,10 @@
           if the action on the server fails.
         """
         # Create a test server. Will be automatically cleaned up on teardown.
-        server = self.create_server(wait_until='SSHABLE')
+        validation_resources = self.get_test_validation_resources(
+            self.os_primary)
+        server = self.create_server(wait_until='SSHABLE', validatable=True,
+                                    validation_resources=validation_resources)
         # Attach the volume to the server and wait for the volume status to be
         # "in-use".
         self.attach_volume(server['id'], volume['id'])