mac80211: call rate_control_send_low() internally

There's no rate control algorithm that *doesn't* want to call
it internally, and calling it internally will let us modify
its behaviour in the future.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/intel/iwlegacy/3945-rs.c

@@ -646,9 +646,6 @@ il3945_rs_get_rate(void *il_r, struct ieee80211_sta *sta, void *il_sta,
 		il_sta = NULL;
 	}
 
-	if (rate_control_send_low(sta, il_sta, txrc))
-		return;
-
 	rate_mask = sta->supp_rates[sband->band];
 
 	/* get user max rate if set */

drivers/net/wireless/intel/iwlegacy/4965-rs.c

@@ -2224,10 +2224,6 @@ il4965_rs_get_rate(void *il_r, struct ieee80211_sta *sta, void *il_sta,
 		il_sta = NULL;
 	}
 
-	/* Send management frames and NO_ACK data using lowest rate. */
-	if (rate_control_send_low(sta, il_sta, txrc))
-		return;
-
 	if (!lq_sta)
 		return;
 

drivers/net/wireless/intel/iwlwifi/dvm/rs.c

@@ -2731,10 +2731,6 @@ static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
 		priv_sta = NULL;
 	}
 
-	/* Send management frames and NO_ACK data using lowest rate. */
-	if (rate_control_send_low(sta, priv_sta, txrc))
-		return;
-
 	rate_idx  = lq_sta->last_txrate_idx;
 
 	if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {

drivers/net/wireless/intel/iwlwifi/mvm/rs.c

@@ -2960,10 +2960,6 @@ static void rs_drv_get_rate(void *mvm_r, struct ieee80211_sta *sta,
 		mvm_sta = NULL;
 	}
 
-	/* Send management frames and NO_ACK data using lowest rate. */
-	if (rate_control_send_low(sta, mvm_sta, txrc))
-		return;
-
 	if (!mvm_sta)
 		return;
 

drivers/net/wireless/realtek/rtlwifi/rc.c

@@ -173,9 +173,6 @@ static void rtl_get_rate(void *ppriv, struct ieee80211_sta *sta,
 	u8 try_per_rate, i, rix;
 	bool not_data = !ieee80211_is_data(fc);
 
-	if (rate_control_send_low(sta, priv_sta, txrc))
-		return;
-
 	rix = _rtl_rc_get_highest_rix(rtlpriv, sta, skb, not_data);
 	try_per_rate = 1;
 	_rtl_rc_rate_set_series(rtlpriv, sta, &rates[0], txrc,