ASoC: arizona: Add support for SNDRV_PCM_RATE_KNOT

The Arizona CODECs support several rates that do not have simple defines
in ALSA. This patch adds support for SNDRV_PCM_RATE_KNOT so that users
can open stream at these rates. As part of this we should always set
constraints in arizona_startup, currently we only set the constraints if
we already have a clock to limit rates to that family of sample rates.
This patch updates this to set a constraint of all rates supported by
the chip if we do not already know which family of rates to limit to.
Finally we also reduce the list of rates supported in the constraints to
only include those that are supported on current parts.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>