man/io_uring.7: style and barrier updates
man/io_uring.7: style and barrier updates

- Don't indent too much, best if it's readable on 80 column displays.

- Update read/write_barrier() to use the usual SMP load_acquire and
  store_release semantics. This is what liburing uses too.

Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>

axboe/liburing,axboe/liburing,axboe/liburing