ASoC: Disable WM8994/58 microphone detection over suspend

It will be non-functional with the basises and clocks off anyway, if the
system needs microphone detection enabled over suspend then it should be
causing the CODEC to ignore suspend using the APIs for that to prevent
the biases being disabled.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>