{nl,cfg,mac}80211: implement dot11MeshHWMPconfirmationInterval

As defined in section 13.10.9.3 Case D (802.11-2012), this
control variable is used to limit the mesh STA to send only
one PREQ to a root mesh STA within this interval of time
(in TUs). The default value for this variable is set to
2000 TUs. However, for current implementation, the maximum
configurable of dot11MeshHWMPconfirmationInterval is
restricted by dot11MeshHWMPactivePathTimeout.

Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com>
[line-break commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 6936fab..b7c3b73 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -2192,6 +2192,10 @@
  * @NL80211_MESHCONF_HWMP_ROOT_INTERVAL: The interval of time (in TUs) between
  *	proactive PREQs are transmitted.
  *
+ * @NL80211_MESHCONF_HWMP_CONFIRMATION_INTERVAL: The minimum interval of time
+ *	(in TUs) during which a mesh STA can send only one Action frame
+ *	containing a PREQ element for root path confirmation.
+ *
  * @__NL80211_MESHCONF_ATTR_AFTER_LAST: internal use
  */
 enum nl80211_meshconf_params {
@@ -2220,6 +2224,7 @@
 	NL80211_MESHCONF_HT_OPMODE,
 	NL80211_MESHCONF_HWMP_PATH_TO_ROOT_TIMEOUT,
 	NL80211_MESHCONF_HWMP_ROOT_INTERVAL,
+	NL80211_MESHCONF_HWMP_CONFIRMATION_INTERVAL,
 
 	/* keep last */
 	__NL80211_MESHCONF_ATTR_AFTER_LAST,