The following fields are added to physical link configuration struct
(snd_soc_tplg_link_config) in ABI v5:

- name and stream name
  Topology will use them to find an existing physical link and configure
  it.

- HW configurations
  Define the types and ABI struct for runtime supported hardware configs
  of physical DAI links, e.g. audio hardware formats. The default HW
  config ID will help topology to find the DAI format to set on init.
  Topology provides this as a fallback if such HW settings are not
  available in ACPI or device tree, to avoid hard code in drivers. It's
  only for config items that can be programmed by SW or FW, not for
  physical things like link connections or GPIO used for HP etc.

- flags and private data
  The flags will be used to configure an existing physical DAI link.
  The private data is reserved for future extension.

NOTE: Current kernel has no support for physical links. A later patch
will add support for configuring physical links and make the support
backward compatible for ABI v4.
Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>