a10s-olinuxino-m fex file improvements

-Default to HMDI out as only a few people will have the optional lcd module
 (and even then there are 3 different types requiring different configs),
 this also matches the default output type used on the a20-olinuxino_micro
-Don't use gpio's on axp, as the sunxi kernels don't support that with
 the axp152 (and trying to uses triggers a WARN_ON)
-Add a leds section for the status led

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