crypto: x86/blowfish - remove redundant assignment to variable nytes

Variable nbytes is being assigned a value that is never read, it is
being re-assigned in the next statement in the while-loop. The
assignment is redundant and can be removed.

Cleans up clang scan-build warnings, e.g.:
arch/x86/crypto/blowfish_glue.c:147:10: warning: Although the value
stored to 'nbytes' is used in the enclosing expression, the value
is never actually read from 'nbytes'

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