man/io_uring_enter.2: add notes about direct open/accept

Add a few lines describing openat/openat2/accept bypassing normal file
tables and installing files right into the fixed file table.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/cf33283b0f2e795ac7f9b6e2eabc70a4f71863c0.1630443189.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 file changed