ieee802154: add simple HardMAC driver sample

fakehard is a really simple driver implementing only necessary
callbacks and serves the role of an example of driver for HardMAC
IEEE 802.15.4 device.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 18c29a8..3f739cf 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2725,6 +2725,8 @@
 
 source "drivers/atm/Kconfig"
 
+source "drivers/ieee802154/Kconfig"
+
 source "drivers/s390/net/Kconfig"
 
 config XEN_NETDEV_FRONTEND