Don't mark SSL_METHOD variable as "const"

The SSL_CTX_new(3) function expects a non-"const" SSL_METHOD value.

plugins/sslutils.c

@@ -48,7 +48,7 @@ int np_net_ssl_init_with_hostname_and_version(int sd, char *host_name, int versi
 }
 
 int np_net_ssl_init_with_hostname_version_and_cert(int sd, char *host_name, int version, char *cert, char *privkey) {
-	const SSL_METHOD *method = NULL;
+	SSL_METHOD *method = NULL;
 
 	switch (version) {
 	case 0: /* Deafult to auto negotiation */