extcon: arizona: Remove duplicate mic ramp configuration

Now this is configured by platform data remove the defualt configuration
the driver had.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>