hostap: Add missing annotations for prism2_bss_list_proc_start() and prism2_bss_list_proc_stop

Sparse reports warnings at prism2_bss_list_proc_start() and prism2_bss_list_proc_stop()

warning: context imbalance in prism2_wds_proc_stop() - unexpected unlock
warning: context imbalance in prism2_bss_list_proc_start() - wrong count at exit

The root cause is the missing annotations at prism2_bss_list_proc_start()

Add the missing __acquires(&local->lock) annotation
Add the missing __releases(&local->lock) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200411001933.10072-4-jbi.octave@gmail.com

drivers/net/wireless/intersil/hostap/hostap_proc.c

@@ -149,6 +149,7 @@ static int prism2_bss_list_proc_show(struct seq_file *m, void *v)
 }
 
 static void *prism2_bss_list_proc_start(struct seq_file *m, loff_t *_pos)
+	__acquires(&local->lock)
 {
 	local_info_t *local = PDE_DATA(file_inode(m->file));
 	spin_lock_bh(&local->lock);
@@ -162,6 +163,7 @@ static void *prism2_bss_list_proc_next(struct seq_file *m, void *v, loff_t *_pos
 }
 
 static void prism2_bss_list_proc_stop(struct seq_file *m, void *v)
+	__releases(&local->lock)
 {
 	local_info_t *local = PDE_DATA(file_inode(m->file));
 	spin_unlock_bh(&local->lock);