Remove some obsolete/obscure internal define switches:

- FLAT_INC
- PKCS1_CHECK (the SSL_OP_PKCS1_CHECK options have been
  no-oped)
- PKCS_TESTVECT (debugging leftovers)
- SSL_AD_MISSING_SRP_USERNAME (unfinished feature)
- DTLS_AD_MISSING_HANDSHAKE_MESSAGE (unfinished feature)
- USE_OBJ_MAC (note this removes a define from the public header but
   very unlikely someone would be depending on it)
- SSL_FORBID_ENULL

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Stephen Henson <steve@openssl.org>
Reviewed-by: Andy Polyakov <appro@openssl.org>
diff --git a/ssl/d1_msg.c b/ssl/d1_msg.c
index ac6d284..a8253b9 100644
--- a/ssl/d1_msg.c
+++ b/ssl/d1_msg.c
@@ -59,23 +59,12 @@
     *ptr++ = s->s3->send_alert[0];
     *ptr++ = s->s3->send_alert[1];
 
-#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
-    if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
-        s2n(s->d1->handshake_read_seq, ptr);
-        l2n3(s->d1->r_msg_hdr.frag_off, ptr);
-    }
-#endif
-
     i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0, &written);
     if (i <= 0) {
         s->s3->alert_dispatch = 1;
         /* fprintf( stderr, "not done with alert\n" ); */
     } else {
-        if (s->s3->send_alert[0] == SSL3_AL_FATAL
-#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
-            || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
-#endif
-            )
+        if (s->s3->send_alert[0] == SSL3_AL_FATAL)
             (void)BIO_flush(s->wbio);
 
         if (s->msg_callback)