Documentation: Move L1TF to separate directory

Documentation: Move L1TF to separate directory

commit 65fd4cb65b2dad97feb8330b6690445910b56d6a upstream.

Move L!TF to a separate directory so the MDS stuff can be added at the
side. Otherwise the all hardware vulnerabilites have their own top level
entry. Should have done that right away.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
[bwh: Backported to 3.16: we never added the documentation, so just update
 the log message]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>