sunxi: Add a CONFIG_CLK_FULL_SPEED define

And use it to set the clockspeed when we've successfully configured the pmic.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
axp209: Various fixes from upstream review

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
axp152: Various fixes from upstream review

Signed-off-by: Hans de Goede <hdegoede@redhat.com>