Prior to this patch, nfs_advlock() did NFSVOPUNLOCK(); return (error);
in many places. This patch replaces these code sequenences with a "goto out;"
and does the NFSVOPUNLOCK(); return (error); at the end of the function
in order to make the vnode locking simpler.
This patch does not change the semantics of nfs_advlock().
Suggested by: kib
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D17853
6ad8a6eaa4