ACPI: tidy up makefile

This patch removes the suggestion that ec.o link order is important,
because it doesn't matter since acpi_ec_init() is no longer an initcall.
And it puts together most of the core modules that are not configurable.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>