at86rf230: add irq low-level for polarity
at86rf230: add irq low-level for polarity

The at86rf2xx chips supports the setting of irq polarity if active low
or active high. This patch adds a handling for IRQ_ACTIVE_LOW if the
irq_type is IRQ_TYPE_LEVEL_LOW.

Signed-off-by: Alexander Aring <d03dbcdedb9639e397df9b8578e8fc8274f4e6c4@gmail.com>
Signed-off-by: Marcel Holtmann <44592b4eea36663c86b994bb0ea99d15309c1c7d@holtmann.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs