Fix type cast in SSL_CTX_set1_groups macro

Fix type cast in SSL_CTX_set1_groups macro

The macro casts the glist parameter to char*
instead of (int *) like the documentation of the function suggest.

Also the function tls1_set_groups that is called from SSL_CTX_ctrl
takes an int * argument. This looks like a copy&paste error from
SSL_CTX_set1_groups_list function.

CLA: trivial
Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/11614)