NFS: Move nfs_idmap.h into fs/nfs/

This file is only used internally to the NFS v4 module, so it doesn't
need to be in the global include path.  I also renamed it from
nfs_idmap.h to nfs4idmap.h to emphasize that it's an NFSv4-only include
file.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index f3ff66e..7d05089 100644
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -11,10 +11,10 @@
 #include <linux/module.h>
 
 #include <linux/sunrpc/metrics.h>
-#include <linux/nfs_idmap.h>
 
 #include "flexfilelayout.h"
 #include "../nfs4session.h"
+#include "../nfs4idmap.h"
 #include "../internal.h"
 #include "../delegation.h"
 #include "../nfs4trace.h"