nfsd: Fix independence of a few nfsd related headers

An header should be compilation independent, .i.e pull in
any header who's declarations are directly used by this header.
And not let users re-include all it's dependencies all over
again.

[At the end of the day what's the use of a header if it does
 not have more then one user?]

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 62f63fb..00a0c81 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -2,6 +2,7 @@
 #define _LINUX_NFS_XDR_H
 
 #include <linux/nfsacl.h>
+#include <linux/nfs3.h>
 
 /*
  * To change the maximum rsize and wsize supported by the NFS client, adjust