mac80211: move TX station pointer and restructure TX

Remove the control.sta pointer from ieee80211_tx_info to free up
sufficient space in the TX skb control buffer for the upcoming
Transmit Power Control (TPC).
Instead, the pointer is now on the stack in a new control struct
that is passed as a function parameter to the drivers' tx method.

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Signed-off-by: Alina Friedrichsen <x-alina@gmx.net>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[reworded commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/rtlwifi/rtl8192ce/trx.c b/drivers/net/wireless/rtlwifi/rtl8192ce/trx.c
index 52166640..390d6d4 100644
--- a/drivers/net/wireless/rtlwifi/rtl8192ce/trx.c
+++ b/drivers/net/wireless/rtlwifi/rtl8192ce/trx.c
@@ -596,7 +596,9 @@
 
 void rtl92ce_tx_fill_desc(struct ieee80211_hw *hw,
 			  struct ieee80211_hdr *hdr, u8 *pdesc_tx,
-			  struct ieee80211_tx_info *info, struct sk_buff *skb,
+			  struct ieee80211_tx_info *info,
+			  struct ieee80211_sta *sta,
+			  struct sk_buff *skb,
 			  u8 hw_queue, struct rtl_tcb_desc *tcb_desc)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
@@ -604,7 +606,6 @@
 	struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw));
 	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
 	bool defaultadapter = true;
-	struct ieee80211_sta *sta;
 	u8 *pdesc = pdesc_tx;
 	u16 seq_number;
 	__le16 fc = hdr->frame_control;