nfsd: make fs/nfsd/vfs.h for common includes

None of this stuff is used outside nfsd, so move it out of the common
linux include directory.

Actually, probably none of the stuff in include/linux/nfsd/nfsd.h really
belongs there, so later we may remove that file entirely.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c
index a713c41..1a259d3 100644
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c
@@ -25,6 +25,7 @@
 #include <linux/nfsd/cache.h>
 #include <linux/nfsd/xdr3.h>
 #include <linux/nfs3.h>
+#include "vfs.h"
 
 #define NFSDDBG_FACILITY		NFSDDBG_PROC