Ensure we create nodes with valid CPU archs

x86 isn't a valid CPU arch, make sure its x86_64

Change-Id: I9b06031c837529840747167a03d8cda750a05998
diff --git a/ironic_tempest_plugin/tests/api/admin/base.py b/ironic_tempest_plugin/tests/api/admin/base.py
index c589461..8850c55 100644
--- a/ironic_tempest_plugin/tests/api/admin/base.py
+++ b/ironic_tempest_plugin/tests/api/admin/base.py
@@ -162,12 +162,12 @@
 
     @classmethod
     @creates('node')
-    def create_node(cls, chassis_id, cpu_arch='x86', cpus=8, local_gb=10,
+    def create_node(cls, chassis_id, cpu_arch='x86_64', cpus=8, local_gb=10,
                     memory_mb=4096, resource_class=None):
         """Wrapper utility for creating test baremetal nodes.
 
         :param chassis_id: The unique identifier of the chassis.
-        :param cpu_arch: CPU architecture of the node. Default: x86.
+        :param cpu_arch: CPU architecture of the node. Default: x86_64.
         :param cpus: Number of CPUs. Default: 8.
         :param local_gb: Disk size. Default: 10.
         :param memory_mb: Available RAM. Default: 4096.
diff --git a/ironic_tempest_plugin/tests/api/admin/test_nodes.py b/ironic_tempest_plugin/tests/api/admin/test_nodes.py
index d5abd11..8d97a8f 100644
--- a/ironic_tempest_plugin/tests/api/admin/test_nodes.py
+++ b/ironic_tempest_plugin/tests/api/admin/test_nodes.py
@@ -111,7 +111,7 @@
 
         _, node = self.create_node(self.chassis['uuid'], **props)
 
-        new_p = {'cpu_arch': 'x86',
+        new_p = {'cpu_arch': 'arm64',
                  'cpus': '1',
                  'local_gb': '10000',
                  'memory_mb': '12300'}