Using extcon USB host mode works properly on DR interface, e.g.
enabling/disabling VBUS. But USB device mode is not working.
Fix this by switching to usb-role-switch instead.

Fixes: dfcd1b6f ("arm64: dts: freescale: add initial device tree for TQMa8MQML with i.MX8MM")
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>