ieee820154: add max csma backoffs setting support

This patch add support for max csma backoffs setting via nl802154
framework.

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 dbccfa9..263095c 100644
--- a/net/ieee802154/rdev-ops.h
+++ b/net/ieee802154/rdev-ops.h
@@ -50,4 +50,13 @@
 					       min_be, max_be);
 }
 
+static inline int
+rdev_set_max_csma_backoffs(struct cfg802154_registered_device *rdev,
+			   struct wpan_dev *wpan_dev,
+			   const u8 max_csma_backoffs)
+{
+	return rdev->ops->set_max_csma_backoffs(&rdev->wpan_phy, wpan_dev,
+						max_csma_backoffs);
+}
+
 #endif /* __CFG802154_RDEV_OPS */