[PATCH 2/2] bugfix: make ss-diff correctly handle tab expansion

[Jason A. Donenfeld]

> len % 8 == 0 ? 8 : (8 - len % 8)


if len % 8 == 0,
    8


8 = 8 - 0
len % 8 := 0
8 = 8 - (len % 8)


so the original formula holds