Platform initialization sets up the LED heartbeat that is controlled
via GPIO.  Requesting the GPIO pins fails, however, as the chip is
only initialized later by a device_initcall().

Fix this up by exporting the initialization function.  Let the
platform set up the chip before it starts using it.
Signed-off-by: NJohannes Weiner <jw@emlix.com>
Signed-off-by: NChris Zankel <chris@zankel.net>