NLM: Move the public declaration of nsm_monitor() to lockd.h

Clean up.

Make the nlm_host argument "const," and move the public declaration to
lockd.h with other NSM public function (nsm_release, eg) and global
variable declarations.

Add a documenting comment.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
index d3c7247..f15a4f5 100644
--- a/include/linux/lockd/lockd.h
+++ b/include/linux/lockd/lockd.h
@@ -242,6 +242,10 @@
 					unsigned int, u32);
 void		  nsm_release(struct nsm_handle *);
 
+/*
+ * Host monitoring
+ */
+int		  nsm_monitor(const struct nlm_host *host);
 
 /*
  * This is used in garbage collection and resource reclaim