Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/Documentation/admin-guide/blockdev/index.rst b/Documentation/admin-guide/blockdev/index.rst
new file mode 100644
index 0000000..b903cf1
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+++ b/Documentation/admin-guide/blockdev/index.rst
@@ -0,0 +1,16 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===========================
+The Linux RapidIO Subsystem
+===========================
+
+.. toctree::
+   :maxdepth: 1
+
+   floppy
+   nbd
+   paride
+   ramdisk
+   zram
+
+   drbd/index