rfc2045: blaze822_multipart: parse rest when boundary is missing

Either the mail got truncated or was wrongly generated, try to go on
by taking the remains of the buffer as part.

rfc2045.c

@@ -182,8 +182,8 @@ blaze822_multipart(struct message *msg, struct message **imsg)
 
 	char *nextpart = mymemmemnl(part, msg->bodyend - part, mboundary, boundarylen);
 	if (!nextpart)
-		return 0;   // XXX error condition
-	if (nextpart == part)  // invalid empty MIME part
+		nextpart = msg->bodyend;  // no boundary found, take all
+	else if (nextpart == part)  // invalid empty MIME part
 		return 0;   // XXX error condition
 
 	if (*(nextpart-1) == '\n')