ARM: dts: sun4i: Enable onboard codec used on the pov protab2-ips9 tablet

The pov protab2-ips9 tablet uses the A10's integrated audio codec,
enable it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>