usb: dwc2: Enable LPM Transaction Received interrupt

Enable "LPM Transaction Received" interrupt for receive an
interrupt when host will send LPM token.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>