ieee820154: add short_addr setting support

This patch adds support for setting short address via nl802154 framework.
Also added a comment because a 0xffff seems to be valid address that we
don't have a short address. This is a valid setting but we need
more checks in upper layers to don't allow this address as source address.
Also the current netlink interface doesn't allow to set the short_addr
to 0xffff. Same for the 0xfffe short address which describes a not
allocated short address.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/ieee802154/rdev-ops.h b/net/ieee802154/rdev-ops.h
index 4115ea2..16b0de0 100644
--- a/net/ieee802154/rdev-ops.h
+++ b/net/ieee802154/rdev-ops.h
@@ -34,4 +34,11 @@
 	return rdev->ops->set_pan_id(&rdev->wpan_phy, wpan_dev, pan_id);
 }
 
+static inline int
+rdev_set_short_addr(struct cfg802154_registered_device *rdev,
+		    struct wpan_dev *wpan_dev, u16 short_addr)
+{
+	return rdev->ops->set_short_addr(&rdev->wpan_phy, wpan_dev, short_addr);
+}
+
 #endif /* __CFG802154_RDEV_OPS */