Large numbers like (1024 * 1024 * 1024) may cost reader/reviewer to
waste one second to convert to 1G.
Introduce kernel include/linux/sizes.h to replace any intermediate
number larger than 4096 (not including 4096) to SZ_*.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
