[ACPI] delete CONFIG_ACPI_BOOT

it has been a synonym for CONFIG_ACPI since 2.6.12

Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index ad67e8f..952ab35 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -15,7 +15,7 @@
 #
 # ACPI Boot-Time Table Parsing
 #
-obj-$(CONFIG_ACPI_BOOT)		+= tables.o
+obj-y				+= tables.o
 obj-$(CONFIG_ACPI_INTERPRETER)	+= blacklist.o
 
 #