smsc: Replace spin_is_locked() with lockdep

lockdep_assert_held() is better suited to checking locking requirements,
since it only checks if the current thread holds the lock regardless of
whether someone else does. This is also a step towards possibly removing
spin_is_locked().
Signed-off-by: Lance Roy <ldr709@gmail.com>
Cc: Steve Glendinning <steve.glendinning@shawell.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <netdev@vger.kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>

drivers/net/ethernet/smsc/smsc911x.h

@@ -67,7 +67,7 @@
 
 #ifdef CONFIG_DEBUG_SPINLOCK
 #define SMSC_ASSERT_MAC_LOCK(pdata) \
-		WARN_ON_SMP(!spin_is_locked(&pdata->mac_lock))
+		lockdep_assert_held(&pdata->mac_lock)
 #else
 #define SMSC_ASSERT_MAC_LOCK(pdata) do {} while (0)
 #endif				/* CONFIG_DEBUG_SPINLOCK */