usb: dwc2: Add clock gating exiting flow by system resume

If not hibernation nor partial power down are supported,
port resume is done using the clock gating programming flow.

Adds a new flow of exiting clock gating when PC is
resumed.

Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210413073723.BA0FEA022E@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>