[PKT_SCHED] ematch: Fix build warning.

Commit 954415e33ed6cfa932c13e8c2460bd05e50723b5 ("[PKT_SCHED] ematch:
tcf_em_destroy robustness") removed a cast on em->data when
passing it to kfree(), but em->data is an integer type that can
hold pointers as well as other values so the cast is necessary.

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

net/sched/ematch.c

···
 			if (em->ops->destroy)
 				em->ops->destroy(tp, em);
 			else if (!tcf_em_is_simple(em))
-				kfree(em->data);
+				kfree((void *) em->data);
 			module_put(em->ops->owner);
 		}
 	}