arm64: tegra: Audio graph sound card for Jetson TX2

Enable support for audio-graph based sound card on Jetson TX2. Based
on the board design following I/O modules are enabled.
  * All I2S instances (I2S1 ... I2S6)
  * All DSPK instances (DSPK1, DSPK2)
  * DMIC1, DMIC2 and DMIC3

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