Remove misleading arguments

method _create_multiple_servers have three parameters in sequence:
'name', 'wait_until' and 'kwargs', however nobody uses the 'name'
and 'wait_until'. Instead it must have kwargs['name'] created/read
then passed to create_test_server(**kwargs).

It is misleading because _create_multiple_servers('foo') won't
create servers which names are or are started with 'foo'.

Cleanupping 'name' and 'wait_until' removes the misleading.

Thanks to Masayuki's suggestion.
Change-Id: Ia9797f9569324b0ad3f40ed332120aab345d560e
diff --git a/tempest/api/compute/servers/test_multiple_create.py b/tempest/api/compute/servers/test_multiple_create.py
index eb1beb1..4dd26af 100644
--- a/tempest/api/compute/servers/test_multiple_create.py
+++ b/tempest/api/compute/servers/test_multiple_create.py
@@ -21,16 +21,10 @@
 class MultipleCreateTestJSON(base.BaseV2ComputeTest):
     _name = 'multiple-create-test'
 
-    def _generate_name(self):
-        return data_utils.rand_name(self._name)
-
-    def _create_multiple_servers(self, name=None, wait_until=None, **kwargs):
-        # NOTE: This is the right way to create_multiple servers and manage to
-        # get the created servers into the servers list to be cleaned up after
-        # all.
-        kwargs['name'] = name if name else self._generate_name()
-        if wait_until:
-            kwargs['wait_until'] = wait_until
+    def _create_multiple_servers(self, **kwargs):
+        # This is the right way to create_multiple servers and manage to get
+        # the created servers into the servers list to be cleaned up after all.
+        kwargs['name'] = kwargs.get('name', data_utils.rand_name(self._name))
         body = self.create_test_server(**kwargs)
 
         return body
diff --git a/tempest/api/compute/servers/test_multiple_create_negative.py b/tempest/api/compute/servers/test_multiple_create_negative.py
index e5b4f46..c4dbe23 100644
--- a/tempest/api/compute/servers/test_multiple_create_negative.py
+++ b/tempest/api/compute/servers/test_multiple_create_negative.py
@@ -22,13 +22,10 @@
 class MultipleCreateNegativeTestJSON(base.BaseV2ComputeTest):
     _name = 'multiple-create-test'
 
-    def _generate_name(self):
-        return data_utils.rand_name(self._name)
-
-    def _create_multiple_servers(self, name=None, wait_until=None, **kwargs):
+    def _create_multiple_servers(self, **kwargs):
         # This is the right way to create_multiple servers and manage to get
         # the created servers into the servers list to be cleaned up after all.
-        kwargs['name'] = kwargs.get('name', self._generate_name())
+        kwargs['name'] = kwargs.get('name', data_utils.rand_name(self._name))
         body = self.create_test_server(**kwargs)
 
         return body