crypto: inside-secure - fix the sha state length in hmac_sha1_setkey

A check is performed on the ipad/opad in the safexcel_hmac_sha1_setkey
function, but the index used by the loop doing it is wrong. It is
currently the size of the state array while it should be the size of a
sha1 state. This patch fixes it.

Fixes: 1b44c5a6

 ("crypto: inside-secure - add SafeXcel EIP197 crypto engine driver")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>