MFC: r225049

MFC: r225049
Fix the NFSv4 server so that it returns NFSERR_SYMLINK when
an attempt to do an Open operation on any type of file other
than VREG is done. A recent discussion on the IETF working group's
mailing list (nfsv4@ietf.org) decided that NFSERR_SYMLINK
should be returned for all non-regular files and not just symlinks,
so that the Linux client would work correctly.
This change does not affect the FreeBSD NFSv4 client and is not
believed to have a negative effect on other NFSv4 clients.

git-svn-id: svn://svn.freebsd.org/base/stable/8@225358 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f