power: supply: sbs-manager: normalize return value of gpio_get

power: supply: sbs-manager: normalize return value of gpio_get

The GPIO get callback is expected to return 0 or 1 (or a negative error
code). Ensure that the value returned by sbsm_gpio_get_value() is
normalized to the [0, 1] range.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://patch.msgid.link/aZYoL2MnTYU5FuQh@google.com
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>