crypto: rockchip - fix scatterlist nents error

crypto: rockchip - fix scatterlist nents error

commit 4359669a087633132203c52d67dd8c31e09e7b2e upstream.

In some cases, the nents of src scatterlist is different from
dst scatterlist. So two variables are used to handle the nents
of src&dst scatterlist.

Reported-by: Eric Biggers <ebiggers@google.com>
Fixes: 433cd2c617bf ("crypto: rockchip - add crypto driver for rk3288")
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: Zhang Zhijie <zhangzj@rock-chips.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>