NFSv4.1: Simplify layout return in pnfs_layout_process()

If the server hands us a layout that does not match the one we currently
hold, then have pnfs_mark_matching_lsegs_return() just ditch the old
layout if NFS_LSEG_LAYOUTRETURN is not set.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/pnfs.c

@@ -2410,9 +2410,7 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
 			.iomode = IOMODE_ANY,
 			.length = NFS4_MAX_UINT64,
 		};
-		pnfs_set_plh_return_info(lo, IOMODE_ANY, 0);
-		pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs,
-						&range, 0);
+		pnfs_mark_matching_lsegs_return(lo, &free_me, &range, 0);
 		goto out_forget;
 	} else {
 		/* We have a completely new layout */