usb: dwc2: reset dwc2 core before dwc2_get_hwparams()

We initiate dwc2 usb controller in BIOS, dwc2_core_reset() should
be called before dwc2_get_hwparams() to reset core registers to
default value. Without this the FIFO setting might be incorrect
because calculating FIFO size need power-on value of
GRXFSIZ/GNPTXFSIZ/HPTXFSIZ registers.

This patch could avoid warnning massage like in rk3288 platform:
[    2.074764] dwc2 ff580000.usb: 256 invalid for
host_perio_tx_fifo_size. Check HW configuration.

Signed-off-by: Yunzhi Li <lyz@rock-chips.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c
index 0bc1c0e..0a584ec 100644
--- a/drivers/usb/dwc2/core.c
+++ b/drivers/usb/dwc2/core.c
@@ -481,7 +481,7 @@
  * Do core a soft reset of the core.  Be careful with this because it
  * resets all the internal state machines of the core.
  */
-static int dwc2_core_reset(struct dwc2_hsotg *hsotg)
+int dwc2_core_reset(struct dwc2_hsotg *hsotg)
 {
 	u32 greset;
 	int count = 0;