[asan] Re-enable a test on i386-darwin.
This test has been reverted in r279918 due to flaky atos support in the OS
some machines in the buildbot fleet were running. This should not be a
problem anymore.
// RUN: %clangxx -O0 %s -o %t
// RUN: %env_tool_opts=strip_path_prefix=/TestCases/ %run %t 2>&1 | FileCheck %s
-// UNSUPPORTED: i386-darwin
//
// Tests __sanitizer_symbolize_pc.
#include <stdio.h>
