bios-linker-loader: move source to common location

There are plans to use bios linker by MIPS, ARM.

It's only used by ACPI ATM, so put it in hw/acpi
and make it depend on CONFIG_ACPI.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/acpi/Makefile.objs

 common-obj-$(CONFIG_ACPI) += core.o piix4.o ich9.o pcihp.o cpu_hotplug.o
 common-obj-$(CONFIG_ACPI) += memory_hotplug.o
 common-obj-$(CONFIG_ACPI) += acpi_interface.o
+common-obj-$(CONFIG_ACPI) += bios-linker-loader.o

hw/i386/Makefile.objs

@@ -7,7 +7,6 @@ obj-$(CONFIG_XEN) += ../xenpv/ xen/
 
 obj-y += kvmvapic.o
 obj-y += acpi-build.o
-obj-y += bios-linker-loader.o
 hw/i386/acpi-build.o: hw/i386/acpi-build.c hw/i386/acpi-dsdt.hex \
 	hw/i386/ssdt-proc.hex hw/i386/ssdt-pcihp.hex hw/i386/ssdt-misc.hex \
 	hw/i386/acpi-dsdt.hex hw/i386/q35-acpi-dsdt.hex \