power: smb135x-charger: Fix usb type detection logic

Fix the usb type detection logic to correctly detect DCP
and HVDCP. Also add workaround to account for SDP being
detected as DCP when booting with no battery.

CRs-Fixed: 1017692
Change-Id: I9aaa99bd1de81dbffc5397d00d20176d4a2a68fc
Signed-off-by: Devesh Jhunjhunwala <deveshj@codeaurora.org>