Merge branch 'for-3.10-async' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull async update from Tejun Heo:
 "This contains three cleanup patches for async from Lai.  All three
  patches are essentially cosmetic."

* 'for-3.10-async' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  async: rename and redefine async_func_ptr
  async: remove unused @node from struct async_domain
  async: simplify lowest_in_progress()