Revert "hwrng: n2-drv - remove casts from void*"

This reverts commit 8b9cfdca9c52f7d39c3ccfac1668e31c20c9f42e.

This patch needs to wait for the HWRNG API to start using void *
for priv first.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/n2-drv.c

@@ -387,7 +387,7 @@ static int n2rng_init_control(struct n2rng *np)
 
 static int n2rng_data_read(struct hwrng *rng, u32 *data)
 {
-	struct n2rng *np = rng->priv;
+	struct n2rng *np = (struct n2rng *) rng->priv;
 	unsigned long ra = __pa(&np->test_data);
 	int len;