UBIFS: use ERR_CAST

Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)).  The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
index 13cb7a4..d12535b 100644
--- a/fs/ubifs/lpt_commit.c
+++ b/fs/ubifs/lpt_commit.c
@@ -646,7 +646,7 @@
 		shft -= UBIFS_LPT_FANOUT_SHIFT;
 		nnode = ubifs_get_nnode(c, nnode, iip);
 		if (IS_ERR(nnode))
-			return ERR_PTR(PTR_ERR(nnode));
+			return ERR_CAST(nnode);
 	}
 	iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
 	return ubifs_get_pnode(c, nnode, iip);