crypto: algboss - remove redundant setting of len to zero

The variable len is set to zero, never read and then later updated
to p - name, so clearly the zero'ing of len is redundant and
can be removed.

Detected by clang scan-build:
" warning: Value stored to 'len' is never read"

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>