[TG3] tg3_bus_string(): remove dead code

The Coverity checker spotted this dead code (note that (clock_ctrl == 7) 
is already handled above).
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/tg3.c

@@ -10543,8 +10543,6 @@ static char * __devinit tg3_bus_string(struct tg3 *tp, char *str)
 			strcat(str, "66MHz");
 		else if (clock_ctrl == 6)
 			strcat(str, "100MHz");
-		else if (clock_ctrl == 7)
-			strcat(str, "133MHz");
 	} else {
 		strcpy(str, "PCI:");
 		if (tp->tg3_flags & TG3_FLAG_PCI_HIGH_SPEED)