bugfix: use ngx_abs() instead of abs() to fix one clang warning (-Wabsolute-value).

Author: agentzh

src/ngx_postgres_output.c

@@ -549,7 +549,7 @@ ngx_postgres_output_chain(ngx_http_request_t *r, ngx_chain_t *cl)
         pglcf = ngx_http_get_module_loc_conf(r, ngx_postgres_module);
         pgctx = ngx_http_get_module_ctx(r, ngx_postgres_module);
 
-        r->headers_out.status = pgctx->status ? abs(pgctx->status)
+        r->headers_out.status = pgctx->status ? ngx_abs(pgctx->status)
                                               : NGX_HTTP_OK;
 
         if (pglcf->output_handler == &ngx_postgres_output_rds) {