sfc: Do not include unneeded headers

Earlier refactoring has made these inclusions unnecessary.

Signed-off-by: Ben Hutchings <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/sfc/net_driver.h

···
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>
 #include <linux/if_vlan.h>
-#include <linux/timer.h>
 #include <linux/mdio.h>
 #include <linux/list.h>
 #include <linux/pci.h>

drivers/net/sfc/selftest.c

···
 #include "nic.h"
 #include "selftest.h"
 #include "workarounds.h"
-#include "spi.h"
-#include "io.h"
 
 /*
  * Loopback test packet structure