crypto: skcipher - in_irq() cleanup

Replace the obsolete and ambiguos macro in_irq() with new
macro in_hardirq().
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/skcipher.c

@@ -431,7 +431,7 @@ static int skcipher_copy_iv(struct skcipher_walk *walk)
 
 static int skcipher_walk_first(struct skcipher_walk *walk)
 {
-	if (WARN_ON_ONCE(in_irq()))
+	if (WARN_ON_ONCE(in_hardirq()))
 		return -EDEADLK;
 
 	walk->buffer = NULL;