On the axg, frddr could only be connected to 1 downstream element, so the
playback was possible on 1 interface only at a time.

On the g12a, the frddr may connect and wait for the request of up to 3
downstream elements. With this, it possible for single playback to be
played on several interfaces at the same time.

Like the toddr fifo, the g12a frddr also need to take care of resetting
the read pointer to the initial fifo address when preparing a playback.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>