ASoC: arizona: Correct checking of FLL ratio limitations

The check to ensure the Fref frequency is within the bounds for the
current ratio, was placed in the wrong loop. The initial configuration
will always be valid and the loop lowering the ratio will only reinforce
this validity. The check should be on the loop increasing the ratio.
This could on occasion cause an invalid ratio/Fref combination to be
selected.

Reported-by: Ryo Tsutsui <ryo.tsutsui@wolfsonmicro.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>