wl12xx: fix Tx security sequence number handling

Do not reset the security sequence number when issuing a join command or
interface is removed. Instead, reset the counter only during the unjoin
command.

Added the notion of counter wrap-around to the LSB number in
wl1271_tx_complete_packet.

Added post recovery padding to adjust for potential security number
progress during the recovery process by the firmware and avoid
potential interop issues in encrypted networks.

Signed-off-by: Oz Krakowski <ozk@ti.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>
diff --git a/drivers/net/wireless/wl12xx/tx.h b/drivers/net/wireless/wl12xx/tx.h
index 832f925..7ed3c01 100644
--- a/drivers/net/wireless/wl12xx/tx.h
+++ b/drivers/net/wireless/wl12xx/tx.h
@@ -150,7 +150,7 @@
 	   (from 1st EDCA AIFS counter until TX Complete). */
 	__le32 medium_delay;
 	/* LS-byte of last TKIP seq-num (saved per AC for recovery). */
-	u8 lsb_security_sequence_number;
+	u8 tx_security_sequence_number_lsb;
 	/* Retry count - number of transmissions without successful ACK.*/
 	u8 ack_failures;
 	/* The rate that succeeded getting ACK