dwc3-msm: Fix compilation errors

This change makes below mentioned code change to fix compliation.
1. Remove usage of dbg_event()
2. Replace busy_slot to trb_enqueue, free_slot to trb_dequeue,
req_queued to started_list, request_list to pending_list, and req->queued
to req->started as those variables are renamed in upstream kernel.
3. Remove usage of multiple event buffer check in dwc3_msm_suspend()
as upstream kernel has removed multiple event buffers related
functionality.
4. dwc3_gadget_ep_get_transfer_index() and dwc3_send_gadget_ep_cmd() APIs
are changed in upstream kernel. Hence fix usage with dwc3-msm.c driver.
5. Add required enums for phy configuration
6. Add MSM specific ep config APIs declarations
7. Remove chg_type usage as it is no more required

Change-Id: I443c1b79af8560820061469dc122b13b90ea536a
Signed-off-by: Mayank Rana <mrana@codeaurora.org>