can: sja1000: remove duplicated includes

Remove duplicated #include('s) in
  drivers/net/can/sja1000/sja1000.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/can/sja1000/sja1000.c

@@ -63,7 +63,6 @@
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
-#include <linux/can/dev.h>
 
 #include "sja1000.h"