mfd: wm5110: Update noise gate default to match the patch file

The default value for the noise gate control register is changed in the
patch file, we need to reflect this in the defaults array, this patch
does so.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>