Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/Documentation/maintainer/pull-requests.rst b/Documentation/maintainer/pull-requests.rst
index 22b271d..1a2f99b 100644
--- a/Documentation/maintainer/pull-requests.rst
+++ b/Documentation/maintainer/pull-requests.rst
@@ -29,7 +29,7 @@
 In order to create the pull request you must first tag the branch that you
 have just created. It is recommended that you choose a meaningful tag name,
 in a way that you and others can understand, even after some time.  A good
-practice is to include in the name an indicator of the sybsystem of origin
+practice is to include in the name an indicator of the subsystem of origin
 and the target kernel version.
 
 Greg offers the following. A pull request with miscellaneous stuff for