[mod_cgi] quiet trace if mod_cgi sends SIGTERM (fixes #2838)

(spurious trace began in lighttpd 1.4.46)

x-ref:
  ".47 always kills git-http-backend"
  https://redmine.lighttpd.net/issues/2838

src/mod_cgi.c

@@ -1027,7 +1027,7 @@ static handler_t cgi_waitpid_cb(server *srv, void *p_d, pid_t pid, int status) {
         }
         else if (WIFSIGNALED(status)) {
             /* ignore SIGTERM if sent by cgi_connection_close() (NULL == hctx)*/
-            if (WTERMSIG(status) != SIGTERM || NULL == hctx) {
+            if (WTERMSIG(status) != SIGTERM || NULL != hctx) {
                 log_error_write(srv, __FILE__, __LINE__, "sdsd", "CGI pid", pid,
                                 "died with signal", WTERMSIG(status));
             }