Update nfsstat to list the NFSv4.2 procedures and operations.

r355677 added NFSv4.2 support to the NFS client and server. It also updated
the nfsstats structure to keep counts for the new procedures (client) and
operations (server) added for NFSv4.2.
This patch updates the "-E" option of nfsstat so that it lists counts for
these new procedures and operations.