ASoC: meson: axg-fifo: relax period size constraints

Now that the fifo depths and thresholds are properly in the axg-fifo
driver, we can relax the constraints on period. As long as the period is a
multiple of the fifo burst size (8 bytes) things should be OK.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20191218172420.1199117-5-jbrunet@baylibre.com


Signed-off-by: Mark Brown <broonie@kernel.org>