MFC r227112:

MFC r227112:

Whenever you boot with nfsv4_server_enable=NO (the default) in rc.conf,
the /etc/rc.d/nfsd script sets vfs.nfsd.server_max_nfsvers to 3.

Then, when you set nfsv4_server_enable=YES in rc.conf, and restart nfsd
via the rc.d script, without rebooting, the sysctl does *not* get reset
to max version 4, so NFSv4 still doesn't work.

Fix this by explicitly setting vfs.nfsd.server_max_nfsvers to 4 when
NFSv4 is requested.

I also added resetting of the nfs_privport sysctls, since this has the
same issue: nfs_reserved_port_only=YES in rc.conf sets the nfs_privport
sysctl to 1, but in the other case, the sysctl doesn't get reset to 0.

Reviewed by:	rmacklem
Silence from:	rc@
Approved by:	re (kib)

git-svn-id: svn://svn.freebsd.org/base/releng/9.0@227608 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f