staging: wilc1000: wilc_wlan.c: remove unused pointer variables

This patch removes unused two pointer variable.
 - Free_head
 - Alloc_head
It's pointer variables unused inside code.
Signed-off-by: Leo Kim <leo.kim@atmel.com>
Signed-off-by: Glen Lee <glen.lee@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wilc1000/wilc_wlan.c

@@ -208,9 +208,6 @@ struct pending_acks_info {
 	struct txq_entry_t  *txqe;
 };
 
-struct ack_session_info *Free_head;
-struct ack_session_info *Alloc_head;
-
 #define NOT_TCP_ACK			(-1)
 
 #define MAX_TCP_SESSION		25