kiwi: Add support for overriding image type attributes

This allows setting things like the volume and application IDs
for ISO builds.

plugins/builder/kiwi.py

@@ -389,6 +389,8 @@ class KiwiCreateImageTask(BaseBuildTask):
             '--description', os.path.join(os.path.basename(scmsrcdir), base_path),
             '--target-dir', target_dir,
         ])
+        for typeattr in self.opts.get('type_attr', [])::
+            cmd.extend(['--set-type-attr', typeattr])
         rv = broot.mock(['--cwd', broot.tmpdir(within=True), '--chroot', '--'] + cmd)
         if rv:
             raise koji.GenericError("Kiwi failed")