ASoC: nau8825: fix invalid configuration in Pre-Scalar of FLL

The clk_ref_div is not configured in the correct position of the
register. The patch fixes that clk_ref_div, Pre-Scalar, is assigned
the wrong value.

Signed-off-by: John Hsu <KCHSU0@nuvoton.com>
Signed-off-by: Mark Brown <broonie@kernel.org>