ARM: STi: DT: STiH410: Add DT nodes for the ehci and ohci usb controllers.

This patch adds the DT nodes for the extra ehci and ohci usb controllers
on the stih410 SoC.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>