power: smb350: Fix dc-online report

When DC jack is plugged in it provides power to the system,
regardless if charging a battery or not.
The device will not shutdown when the battery is empty but dc is online.

Change-Id: If037c2979f95cc4be2bfa28e486bc2af42a67015
Signed-off-by: Amir Samuelov <amirs@codeaurora.org>