Fix import_path circular dependency by splitting it out.

Use import thread_pool instead from, from is evil.

Fix poweroff.out path for ./trace-boot.

build

@@ -10,6 +10,8 @@ import copy
 import shell_helpers
 from shell_helpers import LF
 
+import lkmc
+
 class _Component:
     '''
     Yes, we are re-inventing a crappy dependency resolution system,
@@ -403,7 +405,7 @@ Which components to build. Default: qemu-buildroot
             args = self.get_common_args()
             args.update(extra_args)
             args['show_time'] = False
-            common.import_path_main(component_file)(**args)
+            lkmc.import_path.import_path_main(component_file)(**args)
         return f
 
     def timed_main(self):