This patch adds platform devices for leds. Also export LED related
OPAL API's so that led driver can use these APIs.
Signed-off-by: NVasant Hegde <hegdevasant@linux.vnet.ibm.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>