dt-bindings: mms114: document melfas,mms345l binding

The mms114 driver now supports MMS345L; document the
melfas,mms345l binding that is used for it.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Andi Shyti <andi@etezian.org>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200423102431.2715-2-stephan@gerhold.net


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>