platform/x86/amd/hsmp: Create hsmp/ directory

platform/x86/amd/hsmp: Create hsmp/ directory

This is in preparation to splitting ACPI and platform device drivers.
Create and move hsmp specific code into its own directory,
no logical changes.

Signed-off-by: Suma Hegde <suma.hegde@amd.com>
Reviewed-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20241021111428.2676884-1-suma.hegde@amd.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>