platform/x86: intel_scu_ipcutil: Convert to use new SCU IPC API

Convert the IPC util to use the new SCU IPC API where the SCU IPC
instance is passed to the functions.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>