colibri_imx6: migrate usb to using driver model

Migrate USB to using driver model.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
diff --git a/configs/colibri_imx6_defconfig b/configs/colibri_imx6_defconfig
index 2ab7db4..df5a7be 100644
--- a/configs/colibri_imx6_defconfig
+++ b/configs/colibri_imx6_defconfig
@@ -68,6 +68,7 @@
 CONFIG_DM_REGULATOR_FIXED=y
 CONFIG_IMX_THERMAL=y
 CONFIG_USB=y
+CONFIG_DM_USB=y
 CONFIG_USB_KEYBOARD=y
 CONFIG_USB_GADGET=y
 CONFIG_USB_GADGET_MANUFACTURER="Toradex"