BUG/MINOR: ssl: free the sni_keytype nodes

This patch frees the sni_keytype nodes once the sni_ctxs have been
allocated in ssl_sock_load_multi_ckchn();

Could be backported in every version using the multi-cert SSL bundles.
diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index b9ca662..a957d3e 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -3361,6 +3361,7 @@
 	while (node) {
 		next = ebmb_next(node);
 		ebmb_delete(node);
+		free(ebmb_entry(node, struct sni_keytype, name));
 		node = next;
 	}