Acpica stub

The UEFI poring is achieved by 2 series.
1. improve linking
2. improve portability

This series is mainly to tune the project configurability so that new UEFI acpidump can correctly find objects to link.

Note that the changes are also useful for generic ACPICA development.
The changes include:
1. DEFINE_ACPI_GLOBAS will be required to added for other applications, but better idea should to link utglobal.o than defining DEFINE_ACPI_GLOBALS.
2. AcpiUtInitGlobal() need to be cleaned up first or linking to utglobal.o will lead to many linking requirements for such applications.
3. With utinit.o added for some applications, there turned out to be redundant stub implementations.  This patch cleansup acpiexamples, acpinames.  Note that iasl can also be cleaned up in this way, but this patchset doesn't go that far.
4. acpidump UEFI version should link osPLATxf.c, while also means unix acpidump should link osunixxf.c.  Thus comes the requirement to:
4.1. Eliminate acpidump specific AcpiOsPrintf()/AcpiOsVprintf();
4.2. the possibility to select an AcpiOsMapMemory()/AcpiOsUnmapMemory() implementation;
4.3. Eliminate AeLocalGetRootPointer().
5. Completely deleting stubs will require stubs for AcpiOsThreadId()/AcpiOsExecute.