Always false check

[schmidtw]

I am using the sha1 code in my project & LGTM found that the length == 0 check can't be true ever due to the !length check and return a few lines above.

yubico-c-client/sha1.c

Line 196 in 0107b6e

if (context->Computed || (length >= 8) || (length == 0))