OpenSSL: force meth->name as non-const when we free() it

OpenSSL: force meth->name as non-const when we free() it

We are in control of meth->name (we string_alloc() it in RSA_meth_new())
so we know that we can free() it when it's no longer needed. Yet we have
to force the value to be non-const to avoid a compiler warning -- due to
the fact that OpenSSL defines the value as a const char*, regardless of
its origin.

Acked-by: Steffan Karger <steffan.karger@fox-it.com>
Message-Id: <20170612134330.20971-9-logout@free.fr>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg14798.html

Signed-off-by: Gert Doering <gert@greenie.muc.de>