NFSv4: Document the recover_lost_locks kernel parameter

Rename the new 'recover_locks' kernel parameter to 'recover_lost_locks'
and change the default to 'false'. Document why in
Documentation/kernel-parameters.txt

Move the 'recover_lost_locks' kernel parameter to fs/nfs/super.c to
make it easy to backport to kernels prior to 3.6.x, which don't have
a separate NFSv4 module.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 1eb694e..535011a 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5523,12 +5523,6 @@
 	return err;
 }
 
-bool recover_locks = true;
-module_param(recover_locks, bool, 0644);
-MODULE_PARM_DESC(recover_locks,
-		 "If the server reports that a lock might be lost, "
-		 "try to recovery it risking corruption.");
-
 static int nfs4_lock_expired(struct nfs4_state *state, struct file_lock *request)
 {
 	struct nfs_server *server = NFS_SERVER(state->inode);
@@ -5540,7 +5534,7 @@
 	err = nfs4_set_lock_state(state, request);
 	if (err != 0)
 		return err;
-	if (!recover_locks) {
+	if (!recover_lost_locks) {
 		set_bit(NFS_LOCK_LOST, &request->fl_u.nfs4_fl.owner->ls_flags);
 		return 0;
 	}