Curl_pp_readresp: remove superfluous assignment

Variable already assigned a few lines up.

Detected by cppcheck.

lib/pingpong.c

@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -285,8 +285,6 @@ CURLcode Curl_pp_readresp(curl_socket_t sockfd,
   /* number of bytes in the current line, so far */
   perline = (ssize_t)(ptr-pp->linestart_resp);
 
-  keepon=TRUE;
-
   while((pp->nread_resp<BUFSIZE) && (keepon && !result)) {
 
     if(pp->cache) {