pnfs: add prefix to struct pnfs_layout_segment fields

While we are renaming all the fields, change lo->state to lo->plh_flags.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --cc fs/nfs/nfs4filelayout.c
Simple merge

diff --cc fs/nfs/pnfs.c
Simple merge

diff --cc fs/nfs/pnfs.h
Simple merge