New stuff for 5.3:
- Refactor inode geometry calculation into a single structure instead of
  open-coding pieces everywhere.
- Add online repair to build options.
- Remove unnecessary function call flags and functions.
- Claim maintainership of various loose xfs documentation and header
  files.
- Use struct bio directly for log buffer IOs instead of struct xfs_buf.
- Reduce log item boilerplate code requirements.
- Merge log item code spread across too many files.
- Further distinguish between log item commits and cancellations.
- Various small cleanups to the ag small allocator.
- Support cgroup-aware writeback
- libxfs refactoring for mkfs cleanup
- Remove unneeded #includes
- Fix a memory allocation miscalculation in the new log bio code
- Fix bisection problems
- Fix a crash in ioend processing caused by tripping over freeing of
  preallocated transactions