sfc: Remove redundant casts to and from void *

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/sfc/selftest.c b/drivers/net/sfc/selftest.c
index 2fb69d8..c98f3505 100644
--- a/drivers/net/sfc/selftest.c
+++ b/drivers/net/sfc/selftest.c
@@ -290,7 +290,7 @@
 
 	payload = &state->payload;
 	
-	received = (struct efx_loopback_payload *)(char *) buf_ptr;
+	received = (struct efx_loopback_payload *) buf_ptr;
 	received->ip.saddr = payload->ip.saddr;
 	received->ip.check = payload->ip.check;
 	
@@ -700,7 +700,7 @@
 	 * "flushing" so all inflight packets are dropped */
 	BUG_ON(efx->loopback_selftest);
 	state->flush = 1;
-	efx->loopback_selftest = (void *)state;
+	efx->loopback_selftest = state;
 
 	rc = efx_test_loopbacks(efx, tests, loopback_modes);