platform/x86: intel_cht_int33fe: Convert software node array to group

Code looks and be read cleaner when software nodes are defined individually.
Convert software node array to a group in order to achieve above.

While here, switch struct initializers to C99 standard.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>