dt-bindings: imx-ocotp: Add i.MX8MN compatible

Add compatible for i.MX8MN and add i.MX8MM/i.MX8MN to the description.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20190818093345.29647-2-srinivas.kandagatla@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>