README: Update to sumo release
README: Update to sumo release

Signed-off-by: Pierre-Jean Texier <a4ee2cabad121dc5e19995f1ded171cdfaa10b66@gmail.com>

alexandrebelloni/meta-atmel,linux4sam/meta-atmel,alexandrebelloni/meta-atmel,linux4sam/meta-atmel,linux4sam/meta-atmel,linux4sam/meta-atmel,linux4sam/meta-atmel,alexandrebelloni/meta-atmel