usb: dwc3-msm: add enum for drd_states to remove otg_state usage

otg_state enum defines states for USB OTG devices. Since, driver
supports only role change (DRD) and no OTG support, hence, instead
of using otg_states create separate drd_state enums.

Change-Id: Ifda1fac712e751c980ce51b60b473e5921f2001d
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>