Reduce memory footprint on SGI by putting modules before the kernel

	Reduce memory footprint on SGI by putting modules before the kernel
	as opposed to after.

	* grub-core/Makefile.core.def (kernel): Increase linking address.
	(none_decompress): Likewise.
	(xz_decompress): Likewise.
	* grub-core/boot/mips/startup_raw.S: Use prewritten uncompression
	address.
	* grub-core/kern/mips/arc/init.c (grub_machine_init): Handle memory
	layout change.
	(grub_arch_modules_addr): New function.
	* grub-core/kern/mips/init.c (grub_arch_modules_addr): Moved from here...
	* grub-core/kern/mips/loongson/init.c (grub_arch_modules_addr): .. here
	* grub-core/kern/mips/qemu_mips/init.c (grub_arch_modules_addr): ... and
	here.
	* grub-core/kern/mips/startup.S (total_size): Rename to ...
	(grub_total_modules_size): ... this. Make global.
	[GRUB_MACHINE_ARC]: Don't attempt to move modules out of the bss.
	* include/grub/offsets.h (GRUB_KERNEL_MIPS_LOONGSON_UNCOMPRESSED_ADDR):
	New definition.
	(GRUB_KERNEL_MIPS_QEMU_MIPS_UNCOMPRESSED_ADDR): Likewise.
	(GRUB_KERNEL_MIPS_ARC_UNCOMPRESSED_ADDR): Likewise.
	(GRUB_KERNEL_MACHINE_UNCOMPRESSED_ADDR): Likewise.
	(GRUB_KERNEL_MIPS_ARC_LINK_ADDR): Increased.
	* util/grub-mkimage.c (image_target_desc): New flag
	PLATFORM_FLAGS_MODULES_BEFORE_KERNEL.
	(image_targets): Set PLATFORM_FLAGS_MODULES_BEFORE_KERNEL on mips-arc.
	(generate_image): Handle images with modules before kernel.