mfd: max77686: Remove I2C device ID table

The driver is only used in DT platforms so there's no need to
have an i2c_device_id table.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>