arm64: defconfig: Enable Tegra audio graph card driver

This commit enables Tegra audio graph card driver which is based on
the generic audio-graph card driver. This is intended to be used
on platforms based on Tegra210 and later chips.

Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>