USB: phy-msm-usb: Keep PHY in non driving mode during suspend

Upon cable disconnect, phy must be kept in non driving mode
in device mode. This is to make sure that phy can not interfere
with data lines when external entitiy like pmic is performing
activity during charger detection.

CRs-Fixed: 1086015
Change-Id: I8a199f10cbc812be77b6f38838a1c6f404cbefda
Signed-off-by: Sujeet Kumar <ksujeet@codeaurora.org>