ieee802154: add ack request default handling

This patch introduce a new mib entry which isn't part of 802.15.4 but
useful as default behaviour to set the ack request bit or not if we
don't know if the ack request bit should set. This is currently used for
stacks like IEEE 802.15.4 6LoWPAN.

Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/nl802154.h

@@ -52,6 +52,8 @@ enum nl802154_commands {
 
 	NL802154_CMD_SET_LBT_MODE,
 
+	NL802154_CMD_SET_ACKREQ_DEFAULT,
+
 	/* add new commands above here */
 
 	/* used to define NL802154_CMD_MAX below */
@@ -104,6 +106,8 @@ enum nl802154_attrs {
 
 	NL802154_ATTR_SUPPORTED_COMMANDS,
 
+	NL802154_ATTR_ACKREQ_DEFAULT,
+
 	/* add attributes here, update the policy in nl802154.c */
 
 	__NL802154_ATTR_AFTER_LAST,