crypto: qat - comply with crypto_akcipher_maxsize()

crypto_akcipher_maxsize() asks for the output buffer size without
caring for errors. It allways assume that will be called after
a valid setkey. Comply with it and return what he wants.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/qat/qat_common/qat_asym_algs.c

@@ -1256,11 +1256,11 @@ static int qat_rsa_setprivkey(struct crypto_akcipher *tfm, const void *key,
 	return qat_rsa_setkey(tfm, key, keylen, true);
 }
 
-static int qat_rsa_max_size(struct crypto_akcipher *tfm)
+static unsigned int qat_rsa_max_size(struct crypto_akcipher *tfm)
 {
 	struct qat_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
 
-	return (ctx->n) ? ctx->key_sz : -EINVAL;
+	return ctx->key_sz;
 }
 
 static int qat_rsa_init_tfm(struct crypto_akcipher *tfm)