open() and ESTALE error

[Andrey Alekseyev]

Another correction:
- statement below is valid for a configuration where nfsaccess_cache_timeout
is generally less than acmin, otherwise chances are the failure will be
VOP_OPEN while requesting new attributes by a call to VOP_GETATTR

> which is called from vn_open(). If nfs_access() decides to "go to the wire"
> in #4, it then uses a cached file handle which is indeed stale. Thus,
> open() eventually fails with ESTALE too (ESTALE comes from underlying
> nfs_request()).