usb: dwc3-msm: Remove redundant dwc3_msm_suspend call

dwc3_msm_pm_suspend bails out if DWC is not runtime suspended.
And if it is, it again calls dwc3_msm_suspend which is an
unnecessary call as it also returns if DWC is in LPM.
Remove this unnecssary dwc3_msm_suspend call.

Change-Id: I27a3f430e8c5ebec8eaccf05fe3cd3e3b5f06bce
Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>