pf: Fix osfp configuration

pf_rule_to_krule() incorrectly converted the rule osfp configuration to
the krule structure.

Approved by: re (kib)
Reported by: delphij@
MFC after: 3 days

(cherry picked from commit 2ed689a674c380e48245933d5326da4dda65f94d)
(cherry picked from commit 9823eb6909fcd82bb9d70e77037542e527e3d6ff)