Rework ACPI CST table generation

... in order to unify the Sandybridge and Lenovo implementations
currently used in the tree.

- use acpi_addr_t in acpigen_write_register()
- use acpi_cstate_t for cstate tables (and fix up
  the x60 and t60)
- drop cst_entry from acpigen.h

Change-Id: Icb87418d44d355f607c4a67300107b40f40b3b3f
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/943
Tested-by: build bot (Jenkins)
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>

src/cpu/amd/model_fxx/Makefile.inc

@@ -3,4 +3,4 @@ driver-y += model_fxx_init.c
 ramstage-y += apic_timer.c
 ramstage-y += model_fxx_update_microcode.c
 ramstage-y += processor_name.c
-ramstage-y += powernow_acpi.c
+ramstage-$(CONFIG_GENERATE_ACPI_TABLES) += powernow_acpi.c