MLK-14845 mx6/mx7: Not call usb setup functions used by non-DM driver

MLK-14845 mx6/mx7: Not call usb setup functions used by non-DM driver

Use CONFIG_DM_USB to comment out USB setup functions used by non-DM driver. So
they won't be executed when using DM driver.

These USB setup functions may setup power control pins to USB_PWR function not GPIO,
which is different as the GPIO function used by USB vbus-supply. And cause the power control
not work.

Signed-off-by: Ye Li <ye.li@nxp.com>