add checking for new image metadata property 'hw_cpu_realtime_mask'

This patch adds 'target_version' checking for image metadata
property 'hw_cpu_realtime_mask' and completes test_obj_make_compatible
for this.

Change-Id: Ifbbe7797035eacbabb67384e165843a191a483cc
Closes-Bug: #1533071

nova/objects/image_meta.py

@@ -169,6 +169,8 @@ class ImageMetaProps(base.NovaObject):
         target_version = versionutils.convert_version_to_tuple(target_version)
         if target_version < (1, 11):
             primitive.pop('hw_firmware_type', None)
+        if target_version < (1, 10):
+            primitive.pop('hw_cpu_realtime_mask', None)
         if target_version < (1, 9):
             primitive.pop('hw_cpu_thread_policy', None)
         if target_version < (1, 7):

nova/tests/unit/objects/test_image_meta.py

@@ -282,6 +282,9 @@ class TestImageMetaProps(test.NoDBTestCase):
 
     def test_obj_make_compatible(self):
         props = {
+            'hw_firmware_type': 'uefi',
+            'hw_cpu_realtime_mask': '^0-1',
+            'hw_cpu_thread_policy': 'prefer',
             'img_config_drive': 'mandatory',
             'os_admin_user': 'root',
             'hw_vif_multiqueue_enabled': True,