staging: rtl8712: remove unnecessary braces in while loop

Fixed a linux coding style.

Reported by checkpath:

WARNING: braces {} are not necessary for single statement blocks
Signed-off-by: Hoorad Farrokh <hourrad.f@gmail.com>
Link: https://lore.kernel.org/r/4vmxiuz5u2f2vehngdccj5q7bakpujagk72ty5ounfv2nfzxgr@lqkdn5fecc23Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723bs/core/rtw_sta_mgt.c

@@ -127,9 +127,8 @@ void kfree_all_stainfo(struct sta_priv *pstapriv)
 	phead = get_list_head(&pstapriv->free_sta_queue);
 	plist = get_next(phead);
 
-	while (phead != plist) {
+	while (phead != plist)
 		plist = get_next(plist);
-	}
 
 	spin_unlock_bh(&pstapriv->sta_hash_lock);
 }