net: Remove casts of void *

Unnecessary casts of void * clutter the code.

These are the remainder casts after several specific
patches to remove netdev_priv and dev_priv.

Done via coccinelle script:

$ cat cast_void_pointer.cocci
@@
type T;
T *pt;
void *pv;
@@

- pt = (T *)pv;
+ pt = pv;

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 534c2e5..1b2bb64 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -1201,7 +1201,7 @@
 	int local_cork = 0;
 
 	if (SCTP_EVENT_T_TIMEOUT != event_type)
-		chunk = (struct sctp_chunk *) event_arg;
+		chunk = event_arg;
 
 	/* Note:  This whole file is a huge candidate for rework.
 	 * For example, each command could either have its own handler, so