pmic:battery: Support for Trats Battery at PMIC framework

Trats battery is now treated in the same way as other power related
devices. This approach allows for more unified handling of all devices
responsible for power management.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Stefano Babic <sbabic@denx.de>