linux-phytec-ti

docs: Remove remaining references to metag

Remove any remaining references to the Meta architecture in
Documentation/, primarily from Documentation/features/.

Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-metag@vger.kernel.org
Cc: linux-doc@vger.kernel.org