My earlier commit [1.1169 of pf.c (2023/01/05)] makes pf(4) to report wrong

My earlier commit [1.1169 of pf.c (2023/01/05)] makes pf(4) to report wrong
rule and anchor number when packet matches rule found and anchor depth 2
and more.  The issue has been noticed and reported by Giannis Kapetanakis
(billias _at_ edu.physics.uoc.gr), who also co-developed and tested
the final fix presented in this commit.

To fix the issue pf(4) must also remember the anchor where matching rule
belongs while rules are traversed to find a match for given packet.
The information on anchor is now kept in anchor stack frame.w

OK sthen@