Input: max77693: Add support for Maxim 77843

The Maxim 77843 haptic driver differs from 77693 by:
1. Setting the bias.
2. Different configuration register.
3. Not enabling the low-sys DAC.
4. Using same regmap for PMIC and haptic blocks.

Incorporate all differences into max77693 haptic driver so both devices
can be supported.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>