lib/libcam/cam_cdbparse.3: fix manpage warnings
- Add comma before and after 'e.g.'; remove surrounding parentheses that were unnecessary after this change [1].
- Add .Mt when referencing ken and Peter Dufault's email addresses [2].
- Sprinkle around .An use where proper [2].
Bump .Dd for the change
MFC after: 1 week
Reported by: igor [1], make manlint [2]
Sponsored by: Dell EMC Isilon