Adding sys_get_temp_dir() test specific for Windows.

sys_get_temp_dir() returns a Windows-style path (\\ instead of /) on
Windows. This is why a Windows specific test is required.

Skipping req60524.phpt on Windows. Adding -win32 fork for use only on
Windows.

Fixes test bug #64396.
Merge branch 'PHP-5.5'

* PHP-5.5:
  Adding sys_get_temp_dir() test specific for Windows.