Add -Z time-passes-format to allow specifying a JSON output for -Z time-passes

compiler/rustc_codegen_ssa/src/base.rs

@@ -786,6 +786,8 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
             total_codegen_time,
             start_rss.unwrap(),
             end_rss,
+            tcx.sess.opts.unstable_opts.time_passes_format,
+            true,
         );
     }