iwlagn: fix warning in testmode attribute table

Fix the compile warning cause by [IWL_TM_ATTR_MAX - 1]

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-sv-open.c

@@ -645,7 +645,7 @@ static int iwl_testmode_ownership(struct ieee80211_hw *hw, struct nlattr **tb)
  */
 int iwl_testmode_cmd(struct ieee80211_hw *hw, void *data, int len)
 {
-	struct nlattr *tb[IWL_TM_ATTR_MAX - 1];
+	struct nlattr *tb[IWL_TM_ATTR_MAX];
 	struct iwl_priv *priv = hw->priv;
 	int result;