usb: dwc3: Add snapshot of DWC3 MSM drivers

This change adds dwc3-msm.c and required other QTI MSM
specific driver files. This snapshot is taken as of msm-4.4
commit <9d9cf7636c0d> ("Merge "clk: msm: clock-gpu-cobalt:
Update the GPU PLL FMAXes"").

Change-Id: I00149a0c56d0a5a00a6afe266b691dd9d0ffa992
Signed-off-by: Mayank Rana <mrana@codeaurora.org>