Merge tag 'md/4.1-rc4-fixes' of git://neil.brown.name/md

Pull md bugfixes from Neil Brown:
 "I have a few more raid5 bugfixes pending, but I want them to get a bit
  more review first.  In the meantime:

   - one serious RAID0 data corruption - caused by recent bugfix that
     wasn't reviewed properly.

   - one raid5 fix in new code (a couple more of those to come).

   - one little fix to stop static analysis complaining about silly rcu
     annotation"

* tag 'md/4.1-rc4-fixes' of git://neil.brown.name/md:
  md/bitmap: remove rcu annotation from pointer arithmetic.
  md/raid0: fix restore to sector variable in raid0_make_request
  raid5: fix broken async operation chain