orangefs: do not invalidate attributes on inode create

When an inode is created, we fetch attributes from the server.  There is
no need to turn around and invalidate them.

No need to initialize attributes after the getattr either.  Either it'll
be exactly the same, or it'll be something else and wrong.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>