Upstream: hide_headers_hash inherited regardless of cache settings.

Dependency on cache settings existed prior to 2728c4e4a9ae (0.8.44)
as Set-Cookie header was automatically hidden from responses when
using cache.  This is no longer the case, and hide_headers_hash can
be safely inherited regardless of cache settings.
diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index ceb798f..c2afa0c 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -6021,12 +6021,7 @@
 
         conf->hide_headers_hash = prev->hide_headers_hash;
 
-        if (conf->hide_headers_hash.buckets
-#if (NGX_HTTP_CACHE)
-            && ((conf->cache == 0) == (prev->cache == 0))
-#endif
-           )
-        {
+        if (conf->hide_headers_hash.buckets) {
             return NGX_OK;
         }