krb5 commit: fix crypto openssl hmac warning

[Greg Hudson]

https://github.com/krb5/krb5/commit/efa31786c01bc7be064a6f94c233488c30e4a2dc
commit efa31786c01bc7be064a6f94c233488c30e4a2dc
Author: Gilles Espinasse <g.esp at free.fr>
Date:   Thu May 9 11:58:14 2013 -0400

    fix crypto openssl hmac warning
    
    ticket: 7634

 src/lib/crypto/openssl/hmac.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/src/lib/crypto/openssl/hmac.c b/src/lib/crypto/openssl/hmac.c
index f92ce8b..926790a 100644
--- a/src/lib/crypto/openssl/hmac.c
+++ b/src/lib/crypto/openssl/hmac.c
@@ -105,7 +105,7 @@ krb5int_hmac_keyblock(const struct krb5_hash_provider *hash,
     HMAC_CTX_init(&c);
     HMAC_Init(&c, keyblock->contents, keyblock->length, map_digest(hash));
     for (i = 0; i < num_data; i++) {
-        krb5_crypto_iov *iov = &data[i];
+        const krb5_crypto_iov *iov = &data[i];
 
         if (SIGN_IOV(iov))
             HMAC_Update(&c, (unsigned char*) iov->data.data, iov->data.length);