releasetools: No-op change to use common.AVB_VBMETA_PARTITIONS.

common.AVB_VBMETA_PARTITIONS was recently added (commit
08c190fc89) for the same purpose.

Test: TreeHugger
Change-Id: I65572d54c22a753fdef80677377fcc9b684ee16f

tools/releasetools/add_img_to_target_files.py

@@ -450,7 +450,7 @@ def AddVBMeta(output_zip, partitions, name, needed_partitions):
     if partition not in needed_partitions:
       continue
     assert (partition in common.AVB_PARTITIONS or
-            partition.startswith('vbmeta_')), \
+            partition in common.AVB_VBMETA_PARTITIONS), \
         'Unknown partition: {}'.format(partition)
     assert os.path.exists(path), \
         'Failed to find {} for {}'.format(path, partition)