input: misc: pat9125: add gpio configuration and pinctrl support

Pat9125 is a gpio driven i2c slave. This change adds the gpio
configuration and pinctrl support for pat9125 driver.

Change-Id: I2a9b379715622b5f010a5780ca481da7f9619400
Signed-off-by: Vevek Venkatesan <vevekv@codeaurora.org>
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>