[4.0] 2d511c9 Don't consider backends as resources

[Dridi Boukelmoune]

commit 2d511c90c4c5f3bc0b5b514ceacd95160066acdf
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Thu Apr 7 11:33:41 2016 +0200

    Don't consider backends as resources
    
    Closes #1815

diff --git a/bin/varnishd/cache/cache_pipe.c b/bin/varnishd/cache/cache_pipe.c
index 6507121..7f75a3a 100644
--- a/bin/varnishd/cache/cache_pipe.c
+++ b/bin/varnishd/cache/cache_pipe.c
@@ -116,7 +116,7 @@ PipeRequest(struct req *req, struct busyobj *bo)
 	if (bo->director == NULL) {
 		VSLb(bo->vsl, SLT_FetchError, "No backend");
 		pipecharge(req, &acct_pipe, NULL);
-		SES_Close(req->sp, SC_OVERLOAD);
+		SES_Close(req->sp, SC_TX_ERROR);
 		return;
 	}