usb: dwc3: Suspend USB SS PHY in host mode with device connect case

Currently driver is not suspending USB Super Speed PHY (here USB QMP
PHY) with below usecases.
a. USB super speed HUB is connected and going into bus suspend
b. USB super speed HUB is connected and having USB super speed device
connected on HUB's downstream port

This results into no USB super speed device connect or removal being
detected as autonomous mode is not being enabled with USB QMP PHY.
Fix these issues by suspending USB SS PHY in host mode with device
connect (i.e. HUB or HUB with USB SS device connected) case.

Change-Id: I469b02f0845228f55d9253e7683ea3c133fd9542
Signed-off-by: Mayank Rana <mrana@codeaurora.org>