Fix handling of uncompressed blocks on squashfs and break 4G limit.

	Fix handling of uncompressed blocks on squashfs and break 4G limit.

	* grub-core/fs/squash4.c (grub_squash_super): Add block_size. Remove
	unused flags.
	(grub_squash_inode): Add long_file and block_size.
	(grub_squash_cache_inode): New struct.
	(grub_squash_dirent): Make types into enum.
	(SQUASH_TYPE_LONG_REGULAR): New type.
	(grub_squash_frag_desc): Add field size.
	(SQUASH_BLOCK_FLAGS): New enum.
	(grub_squash_data): Use grub_squash_cache_inode.
	(grub_fshelp_node): Make ino_chunk 64-bit.
	(read_chunk): Minor argument change. All users updated.
	(squash_mount): Use correct le_to_cpu.
	(grub_squash_open): Handle LONG_REGULAR.
	(direct_read): New function.
	(grub_squash_read_data): Handle blocks correctly.