ARM: tegra: Change model of sound card in Nyan Big

Change it from "Acer Chromebook 13" to GoogleNyanBig so it's unique and
identifiable.

With this change the card id exposed to userspace becomes GoogleNyanBig
instead of the current A13.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>