net: drop a space before tabs

Fix a warning from checkpatch.pl:'please no space before tabs'
in include/net/af_unix.h

Signed-off-by: Bo YU <tsu.yubo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/af_unix.h

@@ -40,7 +40,7 @@ struct unix_skb_parms {
 	u32			consumed;
 } __randomize_layout;
 
-#define UNIXCB(skb) 	(*(struct unix_skb_parms *)&((skb)->cb))
+#define UNIXCB(skb)	(*(struct unix_skb_parms *)&((skb)->cb))
 
 #define unix_state_lock(s)	spin_lock(&unix_sk(s)->lock)
 #define unix_state_unlock(s)	spin_unlock(&unix_sk(s)->lock)