The current dm, all non-pci and non-acpi related files are put into
hw/platform directory. This is actually disturbed the meaning of
*platform*. The platform devices are mean of board and SoC specific
non-PCI devices, like usb devices, etc.
This patch refines the ACRN dm directory architecture.
For some common device logic files, likes block_if.c/uart_core.c or
usb_core.c. They will move to hw/ directly.
For platform architecture depended files, create arch/ under root dir.
And create sub-dir arch/x86 for x86 architecture, will create more
architectures in future. The pm.c will move to this new dir.
The hw/acpi will be moved to hw/platform/acpi due to acpi also be
considered as part of platform.
Signed-off-by: Yu Wang <yu1.wang@intel.com>