usb: dwc3-msm: Do not powerdown SSPHY if auto suspend is disabled

On certain platforms, due to a HW issue, the SSPHY keeps
transitioning in and out of p3 whenever we perform any HS
transfers. This leads to a storm of PWR_EVNT irgs.
Fix this by disabling SSPHY autosuspend on such platforms.
Autosuspend will be enabled as part of dwc3_msm_prepare_suspend
so that SSPHY gets a chance to go into P3.

Change-Id: I4e674f780a72a8c4abcb3e6c9f083f23b1faa196
Signed-off-by: Aniket Randive <arandive@codeaurora.org>