[PATCH 2.6.21-rc2] ehca: fix mismatched sync between completion handler and destroy cq

[Roland Dreier]

Looks OK to me, queued for 2.6.21, except:

 > +#include <linux/completion.h>

This can just be <linux/wait.h>, because you're only using
wait_queue_head_t and not struct completion, right?

I fixed this up before merging.