staging: zcache: fix typo "64_BIT"

	depends on CONFIGFS_FS=y && SYSFS=y && !HIGHMEM && ZCACHE=y

	depends on NET

	# must ensure struct page is 8-byte aligned

	select HAVE_ALIGNED_STRUCT_PAGE if !64_BIT

	select HAVE_ALIGNED_STRUCT_PAGE if !64BIT

	default n

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