USB: phy-msm-usb: mark floated charger as DCP type

Previous design marked floated charger as "unknown charger",
mark it now as "DCP charger".

CRs-Fixed: 569939
Change-Id: I7ccbfe2b5677db45b120e0529702218bad70da0c
Signed-off-by: Zhenhua Huang <zhenhuah@codeaurora.org>