[ACPI] IA64 build: blacklist.c is used only on X86

Signed-off-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Len Brown <len.brown@intel.com>
(cherry picked from ef4611613657dfb8af8d336f2f61f08cfcdc9d8a commit)

drivers/acpi/Makefile

@@ -16,7 +16,7 @@ EXTRA_CFLAGS	+= $(ACPI_CFLAGS)
 # ACPI Boot-Time Table Parsing
 #
 obj-y				+= tables.o
-obj-y				+= blacklist.o
+obj-$(CONFIG_X86)		+= blacklist.o
 
 #
 # ACPI Core Subsystem (Interpreter)