platform/x86/intel/sdsi: Change mailbox timeout

On some platforms, it may take up to 400ms for the ready bit to be set in a
successful mailbox transaction. Set the timeout to 500ms to cover the worst
case.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230413013230.1521584-1-david.e.box@linux.intel.com


Signed-off-by: Hans de Goede <hdegoede@redhat.com>