Change signedness of hash in x509_get_sha1_hash(), fixes compiler warning.

Change signedness of hash in x509_get_sha1_hash(), fixes compiler warning.

hash was cast from char * to unsigned char * at the return of the function.
This patch removes the implicit cast by declaring hash as unsigned char * .

Signed-off-by: Steffan Karger <steffan@karger.me>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1398585348-7969-1-git-send-email-steffan@karger.me>
URL: http://article.gmane.org/gmane.network.openvpn.devel/8647
Signed-off-by: Gert Doering <gert@greenie.muc.de>