usb: dwc2: Use AHB burst size parameter

In dwc2_hsotg_core_init_disconnected() function used AHB burst size
parameter, instead of calculating already calculated value.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Razmik Karapetyan <razmik@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>