iwlwifi: support explicit monitor interface

Support explicit monitor interface to keep
injection working after the HW queue changes.
This also finally enables sniffer mode.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c b/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
index 0f7c444..89ccddc 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
@@ -61,6 +61,10 @@
 						  RXON_FILTER_ACCEPT_GRP_MSK;
 		break;
 
+	case NL80211_IFTYPE_MONITOR:
+		ctx->staging.dev_type = RXON_DEV_TYPE_SNIFFER;
+		break;
+
 	default:
 		IWL_ERR(priv, "Unsupported interface type %d\n",
 			ctx->vif->type);