Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.txt
index 70cb68b..6797294 100644
--- a/Documentation/filesystems/dax.txt
+++ b/Documentation/filesystems/dax.txt
@@ -75,8 +75,8 @@
 
 These filesystems may be used for inspiration:
 - ext2: see Documentation/filesystems/ext2.txt
-- ext4: see Documentation/filesystems/ext4.txt
-- xfs:  see Documentation/filesystems/xfs.txt
+- ext4: see Documentation/filesystems/ext4/
+- xfs:  see Documentation/admin-guide/xfs.rst
 
 
 Handling Media Errors