Don't advertise ECC ciphersuits in SSLv2 compatible client hello.

PR#3374
diff --git a/ssl/s23_lib.c b/ssl/s23_lib.c
index 3bf7283..f3c29d1 100644
--- a/ssl/s23_lib.c
+++ b/ssl/s23_lib.c
@@ -107,6 +107,13 @@
 	long l;
 
 	/* We can write SSLv2 and SSLv3 ciphers */
+	/* but no ECC ciphers */
+	if (c->algorithm_mkey == SSL_kECDHr ||
+		c->algorithm_mkey == SSL_kECDHe ||
+		c->algorithm_mkey == SSL_kEECDH ||
+		c->algorithm_auth == SSL_aECDH ||
+		c->algorithm_auth == SSL_aECDSA)
+		return 0;
 	if (p != NULL)
 		{
 		l=c->id;