Create the base set of ACPI structures necessary to satisfy the ACPI subsystem on...

Create the base set of ACPI structures necessary to satisfy the ACPI subsystem on a guest OS.  This includes RSDP, XSDT, FADT, MADT, and DSDT.
The MADT contains a single LSAPIC entry for the
guest CPU.  The DSDT lacks any actual AML content, which the ACPI CA
complains about, but it may be a basis to add more later.  On bootup,
the guest domain now includes a comforting list of ACPI tables:
ACPI: RSDP (v002    XEN                                ) @ 0x0000000000000570
ACPI: XSDT (v001    XEN Xen/ia64 0x00000000 XEN 0x00030000) @ 0x0000000000000594
ACPI: FADT (v003    XEN Xen/ia64 0x00000000 XEN 0x00030000) @ 0x00000000000005c8
ACPI: MADT (v002    XEN Xen/ia64 0x00000000 XEN 0x00030000) @ 0x0000000000000720
ACPI: DSDT (v001    XEN Xen/ia64 0x00000000 XEN 0x00030000) @ 0x0000000000000000
Signed-off-by: Alex Williamson <alex.williamson@hp.com>