It was counter-intuitive that, for pass objects, we logged the
parsed TTL when in fact the ttl visible from vcl was always 0.
In the builtin.vcl the Hit-For-Pass check was also called
for objects already classified as uncacheable.

Now, for passes, we

- do not parse Cache-Control / Expires
  - and, consequently, do not log TTL RFC
- do not call the hfp-code in builtin.vcl
  - and, consequently, do not log TTL VCL

Reflect this in b2.vtc