can: c_can: remove duplicated #include

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

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