ASoC: SOF: Intel: add min/max channels for SSP on Baytrail/Broadwell

Major regressions were detected by SOF CI on CherryTrail and Broadwell:

[   25.705750]  SSP2-Codec: ASoC: no backend playback stream
[   27.923378]  SSP2-Codec: ASoC: no users playback at close - state

This is root-caused to the introduction of the DAI capability checks
with snd_soc_dai_stream_valid(). Its use in soc-pcm.c makes it a
requirement for all DAIs to report at least a non-zero min_channels
field.

For some reason the SSP structures used for SKL+ did provide this
information but legacy platforms didn't.

Fixes: 9b5db059

 ("ASoC: soc-pcm: dpcm: Only allow playback/capture if supported")
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20200417172014.11760-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>