Documentation explaining the motivation, capabilities, and usage
of the new API for tracking system state changes.

Link: http://lkml.kernel.org/r/20191030154313.13263-5-pmladek@suse.com
To: Jiri Kosina
Cc: Kamalesh Babulal
Cc: Nicolai Stange
Cc: live-patching@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Miroslav Benes
Acked-by: Joe Lawrence
Acked-by: Josh Poimboeuf
Signed-off-by: Petr Mladek