ASoC: da7219: Add support for master mode BCLK rate adjustment

Previously the driver would default the BCLK periods per WCLK to
64, to cover all possible non-TDM scenarios when the codec was
DAI clock master. However some devices require a lower BCLK rate
to operate correctly so with this in mind, this commit updates
the code to be more dynamic, with BCLK rate now based on SR and
word length provided to hw_params().

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>