usb: move CONFIG_USB_XHCI_DWC3 to Kconfig

Create an entry for "config USB_XHCI_DWC3" in Kconfig and
switch over to it for all boards.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/configs/xilinx_zynqmp_zcu102_defconfig b/configs/xilinx_zynqmp_zcu102_defconfig
index 6b76dbc..a216f11 100644
--- a/configs/xilinx_zynqmp_zcu102_defconfig
+++ b/configs/xilinx_zynqmp_zcu102_defconfig
@@ -48,6 +48,7 @@
 CONFIG_DEBUG_UART_ANNOUNCE=y
 CONFIG_USB=y
 CONFIG_USB_XHCI_HCD=y
+CONFIG_USB_XHCI_DWC3=y
 CONFIG_USB_DWC3=y
 CONFIG_USB_DWC3_GADGET=y
 CONFIG_USB_ULPI_VIEWPORT=y