usb: dwc2: hcd: initialize hsotg->test_mode upon USB_PORT_FEAT_TEST

Set hsotg->test_mode upon SetPortFeature - USB_PORT_FEAT_TEST, as done in
gadget part, to avoid, in case of using usb role switch, disconnect on
USB_ROLE_NONE (unattach of PIDVID board).

Change-Id: I4cd9f2d4cceacbfb94162f95c32808e1145bdbc1
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Reviewed-on: https://gerrit.st.com/c/mpu/oe/st/linux-stm32/+/214916
Reviewed-by: CIBUILD <MDG-smet-aci-builds@list.st.com>
Reviewed-by: Fabrice GASNIER <fabrice.gasnier@foss.st.com>
Reviewed-by: CITOOLS <MDG-smet-aci-reviews@list.st.com>

Author: ADESTM

drivers/usb/dwc2/hcd.c

@@ -3718,6 +3718,7 @@ static int dwc2_hcd_hub_control(struct dwc2_hsotg *hsotg, u16 typereq,
 			hprt0 &= ~HPRT0_TSTCTL_MASK;
 			hprt0 |= (windex >> 8) << HPRT0_TSTCTL_SHIFT;
 			dwc2_writel(hsotg, hprt0, HPRT0);
+			hsotg->test_mode = windex >> 8;
 			break;
 
 		default: