ASoC: WM8903: Fix mic detection enable logic

The mic detection HW should be enabled when either mic or short detection
is required, not when only both are required.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org