Merge branch 'collectd-5.5'

diff --cc src/write_http.c
index 361c39e4d240bb807158aefa68987183ccddf78d,65197e6c64f1fcedda9e4b75a52a82ffe49860a5..ec3a01ce228aeb7798a611333b90fdb9d2b4630d
--- 1/src/write_http.c
--- 2/src/write_http.c
+++ b/src/write_http.c
@@@ -556,8 -544,8 +562,10 @@@ static int wh_config_node (oconfig_item
          cb->sslversion = CURL_SSLVERSION_DEFAULT;
          cb->low_speed_limit = 0;
          cb->timeout = 0;
 +        cb->log_http_error = 0;
+         cb->headers = NULL;
+ 
 +
          pthread_mutex_init (&cb->send_lock, /* attr = */ NULL);
  
          cf_util_get_string (ci, &cb->name);