greybus: audio_codec: update codec_name as per driver->name

Originally, driver->name was not poluated from GB and thus
manually set from audio_codec driver as a hack.
This is no more required.
Another patch already removes that hack.

Now, with new driver->name as "legacy.<id-bundle.interface>"
codec is registered with different name.
So, during DAI link registration as well it needs modification.

Signed-off-by: Vaibhav Agarwal <vaibhav.agarwal@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>