nfs/filelayout: use pnfs_error_mark_layout_for_return

Instead of calling layoutreturn directly, call pnfs_error_mark_layout_for_return
to mark layouts for return and let generic code return layout when
layout segments are freed.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>

Conflicts:
	fs/nfs/filelayout/filelayout.c
diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
index bfa8547..5d2eadc 100644
--- a/fs/nfs/filelayout/filelayout.c
+++ b/fs/nfs/filelayout/filelayout.c
@@ -200,7 +200,7 @@
 		dprintk("%s DS connection error %d\n", __func__,
 			task->tk_status);
 		nfs4_mark_deviceid_unavailable(devid);
-		set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
+		pnfs_error_mark_layout_for_return(inode, lseg);
 		rpc_wake_up(&tbl->slot_tbl_waitq);
 		/* fall through */
 	default: