Fixed potential leak of temp pool.

In case ngx_hash_add_key() fails, need to goto failed instead of returning,
so that temp_pool will be destoryed.

src/http/ngx_http.c

diff --git a/src/http/ngx_http.c b/src/http/ngx_http.c
index 79ef9c6..a35e9bb 100644
--- a/src/http/ngx_http.c
+++ b/src/http/ngx_http.c
@@ -1469,14 +1469,14 @@
                                   NGX_HASH_WILDCARD_KEY);
 
             if (rc == NGX_ERROR) {
-                return NGX_ERROR;
+                goto failed;
             }
 
             if (rc == NGX_DECLINED) {
                 ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                               "invalid server name or wildcard \"%V\" on %V",
                               &name[n].name, &addr->opt.addr_text);
-                return NGX_ERROR;
+                goto failed;
             }
 
             if (rc == NGX_BUSY) {