vfs: update d_make_root() description

Clearify d_make_root() usage, error handling and cleanup
requirements.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Ian Kent 2019-04-11 12:28:02 +08:00 • committed by Al Viro
commit 8811249f0c