Merge branch 'md-next' of git://git.kernel.org/pub/scm/linux/kernel/git/song/md into...

Pull MD changes from Song.

* 'md-next' of git://git.kernel.org/pub/scm/linux/kernel/git/song/md:
  md/raid1: Replace zero-length array with flexible-array
  md: add a newline when printing parameter 'start_ro' by sysfs
  md: stop using ->queuedata
  md/raid1: release pending accounting for an I/O only after write-behind is also finished
  md: remove redundant memalloc scope API usage
  raid5: update code comment of scribble_alloc()
  raid5: remove gfp flags from scribble_alloc()
  md: use memalloc scope APIs in mddev_suspend()/mddev_resume()
  md: remove the extra line for ->hot_add_disk
  md: flush md_rdev_misc_wq for HOT_ADD_DISK case
  md: don't flush workqueue unconditionally in md_open
  md: add new workqueue for delete rdev
  md: add checkings before flush md_misc_wq