[issue713] shutdown freeze and forced unmounts

[Matthew Dillon]

:So it's getting stuck in dashutdown:
:
:Uptime: 1m13s
:INVOKE(shutdown_post_sync) module_shutdown
:INVOKE(shutdown_post_sync) ahd_shutdown
:INVOKE(shutdown_post_sync) ahd_shutdown
:INVOKE(shutdown_post_sync) dashutdown

    Doh!  A little matter of dashutdown being called after ahd_shutdown
    instead of before!

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>