req: Don't reserve space for htc twice

When struct req changed to no longer store its htc, which was somewhat
hidden in a larger seemingly unrelated change, it ended up being
reserved twice. This looks like a case of starting something, being
interrupted, and starting again.

I decided to remove the one sitting between the reservation of VDP and
VFP contexts since the two are related, and this reservation didn't even
initialize htc.

Refs fee476ac

bin/varnishd/cache/cache_req.c

@@ -153,14 +153,11 @@ Req_New(struct sess *sp)
 	INIT_OBJ(req->vfc, VFP_CTX_MAGIC);
 	p = (void*)PRNDUP(p + sizeof(*req->vfc));
 
-	req->htc = (void*)p;				// XXX: TWICE ?!
-	p = (void*)PRNDUP(p + sizeof(*req->htc));
-
 	req->vdc = (void*)p;
 	memset(req->vdc, 0, sizeof *req->vdc);
 	p = (void*)PRNDUP(p + sizeof(*req->vdc));
 
-	req->htc = (void*)p;				// XXX: TWICE ?!
+	req->htc = (void*)p;
 	INIT_OBJ(req->htc, HTTP_CONN_MAGIC);
 	req->htc->doclose = SC_NULL;
 	p = (void*)PRNDUP(p + sizeof(*req->htc));